Installation Guide

Red Hat Enterprise Linux 5

Installing Red Hat Enterprise Linux 5 for all architectures

Red Hat Engineering Content Services

Red Hat Engineering Content Services

Rüdiger Landmann

Red Hat Engineering Content Services

Jack Reed

Red Hat Engineering Content Services

Petr Bokoč

Red Hat Engineering Content Services

David Cantrell

VNC installation 

Hans De Goede

iSCSI 

Jon Masters

Driver updates 

Edited by

Rüdiger Landmann

Edited by

Jack Reed

Edited by

Petr Bokoč

Abstract

This Installation Guide documents relevant information regarding the installation of Red Hat Enterprise Linux 5.

Part I. x86, AMD64, Intel® 64 and Itanium - Installation and Booting

The Red Hat Enterprise Linux Installation Guide for Intel and AMD 32-bit and 64-bit systems discusses the installation of Red Hat Enterprise Linux and some basic post-installation troubleshooting. Advanced installation options are covered in the second part of this manual.

Chapter 1. Itanium System Specific Information

1.1. Itanium System Installation Overview

Installing Red Hat Enterprise Linux on an Itanium system is different from installing Red Hat Enterprise Linux on an x86-based system. In general, the sequence of steps to a successful installation are the following:
  1. Boot into the Extensible Firmware Interface (EFI) Shell.
  2. If you cannot boot from the CD-ROM, make an LS-120 diskette from the boot image file provided with Red Hat Enterprise Linux.
  3. Using the EFI Shell and the ELILO boot loader, load and run the kernel, and boot into the Red Hat Enterprise Linux installation program.

1.2. Itanium Systems — The EFI Shell

Before you start to install Red Hat Enterprise Linux on an Itanium, you must have a basic understanding of the EFI Shell, what it does, and the information it can provide.
The EFI Shell is a console interface used to launch applications (such as the Red Hat Enterprise Linux installation program), load EFI protocols and device drivers, and execute simple scripts. It is similar to a DOS console and can only access media that is FAT16 (VFAT) formatted.
The EFI Shell also contains common utilities that can be used on the EFI system partition. These utilities include edit, type, cp, rm, and mkdir. For a list of utilities and other commands, type help at the EFI Shell prompt.
The EFI Shell contains a boot loader called ELILO. Additional information on EFI can be found at the following URL:
http://developer.intel.com/technology/efi/index.htm

1.2.1. Itanium Systems — EFI Device Names

The map command can be used to list all devices and file systems that EFI can recognize. When your Itanium system boots into the EFI shell, it probes your system in the following order:
  1. LS-120 drive (if it contains media)
  2. IDE hard drives on the primary IDE interface
  3. IDE hard drives on the secondary IDE interface
  4. SCSI hard drives on the SCSI interface
  5. CD-ROM drives on the IDE interface
  6. CD-ROM drives on the SCSI interface
To view the results of this system poll, type the following command at the EFI Shell prompt:
map
The output is listed in the order the system was probed. So, all FAT16 file systems are listed first, then IDE hard drives, then SCSI hard drives, then IDE CD-ROM drives, and finally SCSI CD-ROM drives.
For example, output of the map command might look like the following:
Device mapping table   
	fs0  : VenHw(Unknown Device:00)/HD(Part1,Sig00000000)   
	fs1  : VenHw(Unknown Device:80)/HD(Part1,Sig00000000)   
	fs2  : VenHw(Unknown Device:FF)/CDROM(Entry1)/HD(Part1,Sig00000000)   
	blk0 : VenHw(Unknown Device:00)   
	blk1 : VenHw(Unknown Device:00)/HD(Part1,Sig00000000)   
	blk2 : VenHw(Unknown Device:80)   
	blk3 : VenHw(Unknown Device:80)/HD(Part1,Sig00000000)   
	blk4 : VenHw(Unknown Device:80)/HD(Part2,Sig00000000)   
	blk5 : VenHw(Unknown Device:80)/HD(Part3,Sig00000000)   
	blk6 : VenHw(Unknown Device:80)/HD(Part3,Sig00000000)/HD(Part1,Sig725F7772)  
	blk7 : VenHw(Unknown Device:FF)   
	blk8 : VenHw(Unknown Device:FF)/CDROM(Entry1)   
	blk9 : VenHw(Unknown Device:FF)/CDROM(Entry1)/HD(Part1,Sig00000000)
In this example, there is an LS-120 diskette in the LS-120 drive as well as a CD-ROM in the CD-ROM drive. All the listings beginning with fs are FAT16 file systems that EFI can read. All the listings beginning with blk are block devices that EFI recognizes. Both the file systems and block devices are listed in the order they are probed. Therefore, fs0 is the system partition on the LS-120, fs1 is the system partition on the hard drive, and fs2 is the system partition on the CD-ROM.

1.2.2. Itanium Systems — EFI System Partition

When partitioning your hard drive for Linux, you must create a system partition that is FAT16 (VFAT) formatted and has a mount point of /boot/efi/. This partition contains the installed Linux kernel(s) as well as the ELILO configuration file (elilo.conf). The elilo.conf file contains a list of kernels from which you can boot your system.

Chapter 2. Steps to Get You Started

2.1. Upgrade or Install?

For information to help you determine whether to perform an upgrade or an installation refer to Chapter 24, Upgrading Your Current System.

2.2. Is Your Hardware Compatible?

Hardware compatibility is particularly important if you have an older system or a system that you built yourself. Red Hat Enterprise Linux 5 should be compatible with most hardware in systems that were factory built within the last two years. However, hardware specifications change almost daily, so it is difficult to guarantee that your hardware is 100% compatible.
The most recent list of supported hardware can be found at:
http://hardware.redhat.com/hcl/

2.3. Do You Have Enough Disk Space?

Nearly every modern-day operating system (OS) uses disk partitions, and Red Hat Enterprise Linux is no exception. When you install Red Hat Enterprise Linux, you may have to work with disk partitions. If you have not worked with disk partitions before (or need a quick review of the basic concepts), refer to Chapter 26, An Introduction to Disk Partitions before proceeding.
The disk space used by Red Hat Enterprise Linux must be separate from the disk space used by other OSes you may have installed on your system, such as Windows, OS/2, or even a different version of Linux. For x86, AMD64, and Intel® 64 systems, at least two partitions (/ and swap) must be dedicated to Red Hat Enterprise Linux. For Itanium systems, at least three partitions (/, /boot/efi/, and swap) must be dedicated to Red Hat Enterprise Linux.
Before you start the installation process, you must
  • have enough unpartitioned[1] disk space for the installation of Red Hat Enterprise Linux, or
  • have one or more partitions that may be deleted, thereby freeing up enough disk space to install Red Hat Enterprise Linux.
To gain a better sense of how much space you really need, refer to the recommended partitioning sizes discussed in Section 4.19.4, “Recommended Partitioning Scheme”.
If you are not sure that you meet these conditions, or if you want to know how to create free disk space for your Red Hat Enterprise Linux installation, refer to Chapter 26, An Introduction to Disk Partitions.

2.4. Can You Install Using the CD-ROM or DVD?

There are several methods that can be used to install Red Hat Enterprise Linux.
Installing from a CD-ROM or DVD requires that you have purchased a Red Hat Enterprise Linux product, you have a Red Hat Enterprise Linux 5.11 CD-ROM or DVD, and you have a DVD/CD-ROM drive on a system that supports booting from it.
If you do not already have a Red Hat Enterprise Linux 5.11 CD set or DVD, you can download one as an ISO image file from the Red Hat Customer Portal. Visit https://access.redhat.com/home and enter your Login and Password. Click on the Downloads link to obtain a list of all currently supported Red Hat Enterprise Linux products. If you do not already have a Login and Password for the Red Hat Customer Portal, visit https://access.redhat.com/downloads/ to purchase a subscription or obtain a free evaluation subscription. When you have obtained the image file, you can burn it to disk with the following procedure:
The exact series of steps that produces a CD from an image file varies greatly from computer to computer, depending on the operating system and disc burning software installed. Use this procedure as a general guide. You might be able to omit certain steps on your computer, or might have to perform some of the steps in a different order from the order described here.
Make sure that your disc burning software is capable of burning discs from image files. Although this is true of most disc burning software, exceptions exist.
In particular, note that the CD burning feature built into Windows XP and Windows Vista cannot burn CDs from images and that earlier Windows operating systems did not have any CD burning capability installed by default. Therefore, if your computer has a Windows operating system installed on it, you need a separate piece of software for this task. Examples of popular CD burning software for Windows that you might already have on your computer include Nero Burning ROM and Roxio Creator. If you use a Windows operating system on your computer and do not have disc burning software installed (or you are not sure that the software can burn discs from image files) InfraRecorder is a suitable alternative available from http://www.infrarecorder.org/, and is free and open-source.
The Disk Utility software installed by default with Mac OS X on Apple computers has the capability to burn CDs from images built into it already. Most widely-used CD burning software for Linux, such as Brasero and K3b, also includes this capability.
  1. Insert a blank, writeable CD into your computer's CD or DVD burner. On some computers, a window opens and displays various options when you insert the disc. If you see a window like this, look for an option to launch your chosen disc burning program. If you do not see an option like this, close the window and launch the program manually.
  2. Launch your disc burning program. On some computers, you can do this by right-clicking (or control-clicking) on the image file and selecting a menu option with a label like Copy image to CD, or Copy CD or DVD image. Other computers might provide you with a menu option to launch your chosen disc burning program, either directly or with an option like Open With. If none of these options are available on your computer, launch the program from an icon on your desktop, in a menu of applications such as the Start menu on Windows operating systems, or in the Mac Applications folder.
  3. In your disc burning program, select the option to burn a CD from an image file. For example, in Nero Burning ROM, this option is called Burn Image and is located on the File menu.
    Note that you can skip this step when using certain CD burning software; for example, Disk Utility on Mac OS X does not require it.
  4. Browse to the disc image file that you downloaded previously and select it for burning.
  5. Click the button that starts the burning process.
Your BIOS may need to be changed to allow booting from your DVD/CD-ROM drive. For more information about changing your BIOS, refer to Section 4.4.1, “Booting the Installation Program on x86, AMD64, and Intel® 64 Systems”.

2.4.1. Alternative Boot Methods

Boot DVD/CD-ROM
If you can boot using the DVD/CD-ROM drive, you can create your own CD-ROM to boot the installation program. This may be useful, for example, if you are performing an installation over a network or from a hard drive. Refer to Section 2.4.2, “Making an Installation Boot CD-ROM” for further instructions.
USB pen drive
If you cannot boot from the DVD/CD-ROM drive, but you can boot using a USB device, such as a USB pen drive, the following alternative boot method is available.
Your system firmware must support booting from a USB device in order for this boot method to work. Refer to the hardware vendor's documentation for details on specifying the device from which the system boots.

Important

When configuring partitions and file systems during installation, ensure you verify the USB device's size, name, and type. The order in which names are assigned to USB-attached storage devices can vary because certain devices may take longer to initialize than others. Consequently, a device may receive a different name than you expect, such as sdc instead of sda.
  1. Make a copy of the Red Hat Enterprise Linux 5 installation files available. Either:
    • Insert the Red Hat Enterprise Linux 5 installation DVD or CD-ROM#1.
    • Mount an image of the Red Hat Enterprise Linux 5 installation DVD or CD-ROM#1.
    • Ensure that the installation files are available on a network location accessible by your system, for example, on an NFS share that it can access.
  2. Attach a USB flash drive to your system. The following steps presume a system that runs Red Hat Enterprise Linux 5.
  3. Run dmesg to identify the device name for the drive. If you run dmesg shortly after you attach the drive, the device name appears in the most recent lines of output. For example, the following dmesg output shows a flash drive that receives the device name /dev/sdb:
    Initializing USB Mass Storage driver...
    scsi2 : SCSI emulation for USB Mass Storage devices
    usb-storage: device found at 5
    usb-storage: waiting for device to settle before scanning
    usbcore: registered new driver usb-storage
    USB Mass Storage support registered.
      Vendor: USB 2.0   Model: Flash Disk        Rev: 5.00
      Type:   Direct-Access                      ANSI SCSI revision: 02
    SCSI device sdb: 2043904 512-byte hdwr sectors (1046 MB)
    sdb: Write Protect is off
    sdb: Mode Sense: 0b 00 00 08
    sdb: assuming drive cache: write through
    SCSI device sdb: 2043904 512-byte hdwr sectors (1046 MB)
    sdb: Write Protect is off
    sdb: Mode Sense: 0b 00 00 08
    sdb: assuming drive cache: write through
    sdb: sdb1
    sd 2:0:0:0: Attached scsi removable disk sdb
    sd 2:0:0:0: Attached scsi generic sg1 type 0
    usb-storage: device scan complete
  4. Unmount any partitions on the flash drive that are currently mounted. It is likely that your system automatically mounted any available partitions when you attached the flash drive.
    1. Use the mount command to find any mounted partitions on the flash drive. For example, the following output shows a single partition on /dev/sdb is mounted, the partition named /dev/sdb1:
      $ mount
      /dev/mapper/VolGroup00-LogVol00 on / type ext3 (rw)
      proc on /proc type proc (rw)
      sysfs on /sys type sysfs (rw)
      devpts on /dev/pts type devpts (rw,gid=5,mode=620)
      tmpfs on /dev/shm type tmpfs (rw,rootcontext="system_u:object_r:tmpfs_t:s0")
      /dev/sda1 on /boot type ext3 (rw)
      none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
      sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
      /dev/sdb1 on /media/BOOTUSB type vfat (rw,nosuid,nodev,uid=500,utf8,shortname=mixed,flush)
    2. Unmount partitions with the umount command. For example, to unmount /dev/sdb1, run:
      umount /dev/sdb1
      Run umount for each partition on the flash drive that is mounted.
  5. Use fdisk to partition the flash drive to contain a single partition only, with the following parameters:
    1. numbered 1.
    2. partition type is set to b (W95 FAT32).
    3. flagged as bootable.
  6. Run mkdosfs to format the partition created in the previous step as FAT. For example:
    mkdosfs /dev/sdb1
  7. Mount the partition. For example:
    mount /dev/sdb1 /mnt
  8. Copy the contents of the isolinux/ directory of the installation DVD or CD-ROM#1 onto the flash drive.
  9. Rename the configuration file from isolinux.cfg to syslinux.cfg. For example, if the flash drive is mounted on /mnt, run:
    cd /mnt/; mv isolinux.cfg syslinux.cfg
    1. If necessary, edit syslinux.cfg for your particular environment. For example, to configure the installation to use a kickstart file shared over NFS, specify:
      linux ks=nfs:://ks.cfg
  10. Copy the images/pxeboot/initrd.img file from the installation DVD or CD-ROM#1 onto the flash drive.
  11. Unmount the flash drive. For example:
    umount /dev/sdb1
  12. Make the USB flash drive bootable. For example:
    syslinux /dev/sdb1
  13. Mount the flash drive again. For example:
    mount /dev/sdb1 /mnt
  14. Install the GRUB boot loader on the USB flash drive. For example:
    grub-install --root-directory=/mnt /dev/sdb
  15. Verify that the USB flash drive has a /boot/grub directory. If it does not, create the directory manually; for example:
    mkdir -p /mnt/boot/grub
  16. Create the boot/grub/grub.conf file on the flash drive as follows:
    default=0
    timeout=5
    root (hd1,0)
    title Red Hat Enterprise Linux installer
    kernel /vmlinuz
    initrd /initrd.img
  17. Unmount the flash drive. For example:
    umount /dev/sdb1
  18. Detach the USB flash drive.
  19. Attach the USB disk to the system on which you wish to install Red Hat Enterprise Linux.
  20. Boot the target system from the USB flash drive.

2.4.2. Making an Installation Boot CD-ROM

isolinux (not available for Itanium systems) is used for booting the Red Hat Enterprise Linux installation CD. To create your own CD-ROM to boot the installation program, use the following instructions:
Copy the isolinux/ directory from the Red Hat Enterprise Linux DVD or CD #1 into a temporary directory (referred to here as <path-to-workspace>) using the following command:
cp -r <path-to-cd>/isolinux/ <path-to-workspace>
Change directories to the <path-to-workspace> directory you have created:
cd <path-to-workspace>
Make sure the files you have copied have appropriate permissions:
chmod u+w isolinux/*
Finally, issue the following command to create the ISO image file:
mkisofs -o file.iso -b isolinux.bin -c boot.cat -no-emul-boot \  
-boot-load-size 4 -boot-info-table -R -J -v -T isolinux/

Note

The above command was split into two lines for printing purposes only. When you execute this command, be sure to type it as a single command, all on the same line.
Burn the resulting ISO image (named file.iso and located in <path-to-workspace>) to a CD-ROM as you normally would.

2.5. Preparing for a Network Installation

Ensure that you have boot media available on CD, DVD, or a USB storage device such as a flash drive.
The Red Hat Enterprise Linux installation media must be available for either a network installation (via NFS, FTP, or HTTP) or installation via local storage. Use the following steps if you are performing an NFS, FTP, or HTTP installation.
The NFS, FTP, or HTTP server to be used for installation over the network must be a separate machine which can provide the complete contents of the installation DVD-ROM or the installation CD-ROMs.

Note

The Red Hat Enterprise Linux installation program has the ability to test the integrity of the installation media. It works with the CD, DVD, hard drive ISO, and NFS ISO installation methods. Red Hat recommends that you test all installation media before starting the installation process, and before reporting any installation-related bugs (many of the bugs reported are actually due to improperly-burned CDs). To use this test, type the following command at the boot: prompt (prepend with elilo for Itanium systems):
linux mediacheck

Note

In the following examples, the directory on the installation staging server that will contain the installation files will be specified as /location/of/disk/space. The directory that will be made publicly available via FTP, NFS, or HTTP will be specified as /publicly/available/directory. For example, /location/of/disk/space may be a directory you create called /var/isos. /publicly/available/directory might be /var/www/html/rhel5, for an HTTP install.
To copy the files from the installation DVD or CD-ROMs to a Linux machine which acts as an installation staging server, perform the following steps:
  • Create an iso image from the installation disk(s) using the following command (for DVDs):
    dd if=/dev/dvd of=/location/of/disk/space/RHEL5.iso
    where dvd refers to your DVD drive device.

2.5.1. Preparing for FTP and HTTP installation

If you are setting up an installation tree for NFS, FTP, or HTTP installations, you must copy the RELEASE-NOTES files and all files from the RedHat directory on all operating systems ISO images. On Linux and UNIX systems, the following process will properly configure the target directory on your server (repeat for each CD-ROM/ISO image):
  1. Insert CD-ROM or DVD-ROM.
  2. mount /media/cdrom
  3. If you are installing the Server variant, run cp -a /media/cdrom/Server <target-directory>
    If you are installing the Client variant, run cp -a /media/cdrom/Client <target-directory>
  4. cp /media/cdrom/RELEASE-NOTES* <target-directory> (Installation CD 1 or DVD only)
  5. cp /media/cdrom/images <target-directory> (Installation CD 1 or DVD only)
  6. umount /media/cdrom
(Where <target-directory> represents the path to the directory to contain the installation tree.)

Note

Do not copy the Supplementary ISO image, or any of the layered product ISO images, as this will overwrite files necessary for Anaconda's proper operation.
These ISO images must be installed after Red Hat Enterprise Linux has been installed.
Next make sure that the /publicly/available/directory directory is shared via FTP or HTTP, and verify client access. You can check to see whether the directory is accessible from the server itself, and then from another machine on the same subnet that you will be installing to.

2.5.2. Preparing for an NFS install

For NFS installation it is not necessary to mount the iso image. It is sufficient to make the iso image itself available via NFS. You can do this by moving the iso image or images to the NFS exported directory:
  • For DVD:
    mv /location/of/disk/space/RHEL5.iso /publicly/available/directory/
  • For CDROMs:
    mv /location/of/disk/space/disk*.iso /publicly/available/directory/
Ensure that the /publicly/available/directory directory is exported via NFS via an entry in /etc/exports.
To export to a specific system:
/publicly/available/directory client.ip.address
To export to all systems use an entry such as:
/publicly/available/directory *
Start the NFS daemon (on a Red Hat Enterprise Linux system, use /sbin/service nfs start). If NFS is already running, reload the configuration file (on a Red Hat Enterprise Linux system use /sbin/service nfs reload).
Be sure to test the NFS share following the directions in the Red Hat Enterprise Linux Deployment Guide.

2.6. Preparing for a Hard Drive Installation

Note

Hard drive installations only work from ext2, ext3, or FAT file systems. If you have a file system other than those listed here, such as reiserfs, you will not be able to perform a hard drive installation.
Hard drive installations require the use of the ISO (or DVD/CD-ROM) images. An ISO image is a file containing an exact copy of a DVD/CD-ROM image. After placing the required ISO images (the binary Red Hat Enterprise Linux DVD/CD-ROMs) in a directory, choose to install from the hard drive. You can then point the installation program at that directory to perform the installation.
Ensure that you have boot media available on CD, DVD, or a USB storage device such as a flash drive.
To prepare your system for a hard drive installation, you must set the system up in one of the following ways:
  • Using a set of CD-ROMs, or a DVD — Create ISO image files from each installation CD-ROM, or from the DVD. For each CD-ROM (once for the DVD), execute the following command on a Linux system:
    dd if=/dev/cdrom of=/tmp/file-name.iso
  • Using ISO images — transfer these images to the system to be installed.
    Verifying that ISO images are intact before you attempt an installation, helps to avoid problems. To verify the ISO images are intact prior to performing an installation, use an md5sum program (many md5sum programs are available for various operating systems). An md5sum program should be available on the same Linux machine as the ISO images.

Note

The Red Hat Enterprise Linux installation program has the ability to test the integrity of the installation media. It works with the CD / DVD, hard drive ISO, and NFS ISO installation methods. Red Hat recommends that you test all installation media before starting the installation process, and before reporting any installation-related bugs (many of the bugs reported are actually due to improperly-burned CDs). To use this test, type the following command at the boot: prompt (prepend with elilo for Itanium systems):
linux mediacheck
Additionally, if a file called updates.img exists in the location from which you install, it is used for updates to anaconda, the installation program. Refer to the file install-methods.txt in the anaconda RPM package for detailed information on the various ways to install Red Hat Enterprise Linux, as well as how to apply the installation program updates.


[1] Unpartitioned disk space means that available disk space on the hard drive(s) you are installing to has not been divided into sections for data. When you partition a disk, each partition behaves like a separate disk drive.

Chapter 3. System Specifications List

The most recent list of supported hardware can be found at http://hardware.redhat.com/hcl/.
This system specifications list will help you keep a record of your current system settings and requirements. Enter the corresponding information about your system in the list provided below as a handy reference to help make your Red Hat Enterprise Linux installation goes smoothly.
  • hard drive(s): type, label, size; e.g. IDE hda=40 GB
  • partitions: map of partitions and mount points; e.g. /dev/hda1=/home, /dev/hda2=/ (fill this in once you know where they will reside)
  • memory: amount of RAM installed on your system; e.g. 512 MB, 1 GB
  • CD-ROM: interface type; e.g. SCSI, IDE (ATAPI)
  • SCSI adapter: if present, make and model number; e.g. BusLogic SCSI Adapter, Adaptec 2940UW
  • network card: if present, make and model number; e.g. Tulip, 3COM 3C590
  • mouse: type, protocol, and number of buttons; e.g. generic 3 button PS/2 mouse, MouseMan 2 button serial mouse
  • monitor: make, model, and manufacturer specifications; e.g. Optiquest Q53, ViewSonic G773
  • video card: make, model number and size of VRAM; e.g. Creative Labs Graphics Blaster 3D, 8MB
  • sound card: make, chipset and model number; e.g. S3 SonicVibes, Sound Blaster 32/64 AWE
  • IP, DHCP, and BOOTP addresses
  • netmask
  • gateway IP address
  • one or more name server IP addresses (DNS)
  • domain name: the name given to your organization; e.g. example.com
  • hostname: the name of your computer; your personal choice of names; e.g. cookie, southpark
If any of these networking requirements or terms are unfamiliar to you, contact your network administrator for assistance.

Chapter 4. Installing on Intel® and AMD Systems

This chapter explains how to perform a Red Hat Enterprise Linux installation from the DVD/CD-ROM, using the graphical, mouse-based installation program. The following topics are discussed:
  • Becoming familiar with the installation program's user interface
  • Starting the installation program
  • Selecting an installation method
  • Configuration steps during the installation (language, keyboard, mouse, partitioning, etc.)
  • Finishing the installation

4.1. The Graphical Installation Program User Interface

If you have used a graphical user interface (GUI) before, you are already familiar with this process; use your mouse to navigate the screens, click buttons, or enter text fields.
You can also navigate through the installation using the keyboard. The Tab key allows you to move around the screen, the Up and Down arrow keys to scroll through lists, + and - keys expand and collapse lists, while Space and Enter selects or removes from selection a highlighted item. You can also use the Alt+X key command combination as a way of clicking on buttons or making other screen selections, where X is replaced with any underlined letter appearing within that screen.

Note

If you are using an x86, AMD64, or Intel® 64 system, and you do not wish to use the GUI installation program, the text mode installation program is also available. To start the text mode installation program, use the following command at the boot: prompt:
linux text
Refer to Section 4.3, “The Text Mode Installation Program User Interface” for a brief overview of text mode installation instructions.
It is highly recommended that installs be performed using the GUI installation program. The GUI installation program offers the full functionality of the Red Hat Enterprise Linux installation program, including LVM configuration which is not available during a text mode installation.
Users who must use the text mode installation program can follow the GUI installation instructions and obtain all needed information.

Note

If you are using an Itanium system, and you do not wish to use the GUI installation program, the text mode installation program is also available. To start the text mode installation program, type the following command at the EFI Shell prompt:
elilo linux text

4.1.1. A Note about Virtual Consoles

The Red Hat Enterprise Linux installation program offers more than the dialog boxes of the installation process. Several kinds of diagnostic messages are available to you, as well as a way to enter commands from a shell prompt. The installation program displays these messages on five virtual consoles, among which you can switch using a single keystroke combination.
A virtual console is a shell prompt in a non-graphical environment, accessed from the physical machine, not remotely. Multiple virtual consoles can be accessed simultaneously.
These virtual consoles can be helpful if you encounter a problem while installing Red Hat Enterprise Linux. Messages displayed on the installation or system consoles can help pinpoint a problem. Refer to Table 4.1, “Console, Keystrokes, and Contents” for a listing of the virtual consoles, keystrokes used to switch to them, and their contents.
Generally, there is no reason to leave the default console (virtual console #6) for graphical installations unless you are attempting to diagnose installation problems.

Table 4.1. Console, Keystrokes, and Contents

console keystrokes contents
1 ctrl+alt+f1 installation dialog
2 ctrl+alt+f2 shell prompt
3 ctrl+alt+f3 install log (messages from installation program)
4 ctrl+alt+f4 system-related messages
5 ctrl+alt+f5 other messages
6 ctrl+alt+f6 x graphical display

4.2. Screenshots during installation

Anaconda allows you to take screenshots during the installation process. At any time during installation, press Shift+Print Screen and anaconda will save a screenshot to /root/anaconda-screenshots.
If you are performing a Kickstart installation, use the autostep --autoscreenshot option to generate a screenshot of each step of the installation automatically. Refer to Section 31.3, “Creating the Kickstart File” for details of configuring a Kickstart file.

4.3. The Text Mode Installation Program User Interface

The Red Hat Enterprise Linux text mode installation program uses a screen-based interface that includes most of the on-screen widgets commonly found on graphical user interfaces. Figure 4.1, “Installation Program Widgets as seen in Boot Loader Configuration, and Figure 4.2, “Installation Program Widgets as seen in Disk Druid, illustrate the screens that appear during the installation process.

Note

While text mode installations are not explicitly documented, those using the text mode installation program can easily follow the GUI installation instructions. One thing to note is that manipulation of LVM (Logical Volume Management) disk volumes is only possible in graphical mode. In text mode it is only possible to view and accept the default LVM setup.
Installation Program Widgets as seen in Boot Loader Configuration

Figure 4.1. Installation Program Widgets as seen in Boot Loader Configuration

Installation Program Widgets as seen in Disk Druid

Figure 4.2. Installation Program Widgets as seen in Disk Druid

  • Window — Windows (usually referred to as dialogs in this manual) appear on your screen throughout the installation process. At times, one window may overlay another; in these cases, you can only interact with the window on top. When you are finished in that window, it disappears, allowing you to continue working in the window underneath.
  • Checkbox — Checkboxes allow you to select or deselect a feature. The box displays either an asterisk (selected) or a space (unselected). When the cursor is within a checkbox, press Space to select or deselect a feature.
  • Text Input — Text input lines are regions where you can enter information required by the installation program. When the cursor rests on a text input line, you may enter and/or edit information on that line.
  • Text Widget — Text widgets are regions of the screen for the display of text. At times, text widgets may also contain other widgets, such as checkboxes. If a text widget contains more information than can be displayed in the space reserved for it, a scroll bar appears; if you position the cursor within the text widget, you can then use the Up and Down arrow keys to scroll through all the information available. Your current position is shown on the scroll bar by a # character, which moves up and down the scroll bar as you scroll.
  • Scroll Bar — Scroll bars appear on the side or bottom of a window to control which part of a list or document is currently in the window's frame. The scroll bar makes it easy to move to any part of a file.
  • Button Widget — Button widgets are the primary method of interacting with the installation program. You progress through the windows of the installation program by navigating these buttons, using the Tab and Enter keys. Buttons can be selected when they are highlighted.
  • Cursor — Although not a widget, the cursor is used to select (and interact with) a particular widget. As the cursor is moved from widget to widget, it may cause the widget to change color, or the cursor itself may only appear positioned in or next to the widget.

4.3.1. Using the Keyboard to Navigate

Navigation through the installation dialogs is performed through a simple set of keystrokes. To move the cursor, use the Left, Right, Up, and Down arrow keys. Use Tab, and Shift-Tab to cycle forward or backward through each widget on the screen. Along the bottom, most screens display a summary of available cursor positioning keys.
To "press" a button, position the cursor over the button (using Tab, for example) and press Space or Enter. To select an item from a list of items, move the cursor to the item you wish to select and press Enter. To select an item with a checkbox, move the cursor to the checkbox and press Space to select an item. To deselect, press Space a second time.
Pressing F12 accepts the current values and proceeds to the next dialog; it is equivalent to pressing the OK button.

Warning

Unless a dialog box is waiting for your input, do not press any keys during the installation process (doing so may result in unpredictable behavior).

4.4. Starting the Installation Program

To start, first make sure that you have all necessary resources for the installation. If you have already read through Chapter 2, Steps to Get You Started, and followed the instructions, you should be ready to start the installation process. When you have verified that you are ready to begin, boot the installation program using the Red Hat Enterprise Linux DVD or CD-ROM #1 or any boot media that you have created.

Note

Occasionally, some hardware components require a driver diskette during the installation. A driver diskette adds support for hardware that is not otherwise supported by the installation program. Refer to Chapter 7, Updating drivers during installation on Intel and AMD systems for more information.

4.4.1. Booting the Installation Program on x86, AMD64, and Intel® 64 Systems

You can boot the installation program using any one of the following media (depending upon what your system can support):
  • Red Hat Enterprise Linux DVD/CD-ROM — Your machine supports a bootable DVD/CD-ROM drive and you have the Red Hat Enterprise Linux CD-ROM set or DVD.
  • Boot CD-ROM — Your machine supports a bootable CD-ROM drive and you want to perform network or hard drive installation.
  • USB pen drive — Your machine supports booting from a USB device.
  • PXE boot via network — Your machine supports booting from the network. This is an advanced installation path. Refer to Chapter 34, PXE Network Installations for additional information on this method.
To create a boot CD-ROM or to prepare your USB pen drive for installation, refer to Section 2.4.1, “Alternative Boot Methods”.
Insert the boot media and reboot the system. Your BIOS settings may need to be changed to allow you to boot from the CD-ROM or USB device.

Note

To change your BIOS settings on an x86, AMD64, or Intel® 64 system, watch the instructions provided on your display when your computer first boots. A line of text appears, telling you which key to press to enter the BIOS settings.
Once you have entered your BIOS setup program, find the section where you can alter your boot sequence. The default is often C, A or A, C (depending on whether you boot from your hard drive [C] or a diskette drive [A]). Change this sequence so that the CD-ROM is first in your boot order and that C or A (whichever is your typical boot default) is second. This instructs the computer to first look at the CD-ROM drive for bootable media; if it does not find bootable media on the CD-ROM drive, it then checks your hard drive or diskette drive.
Save your changes before exiting the BIOS. For more information, refer to the documentation that came with your system.
After a short delay, a screen containing the boot: prompt should appear. The screen contains information on a variety of boot options. Each boot option also has one or more help screens associated with it. To access a help screen, press the appropriate function key as listed in the line at the bottom of the screen.
As you boot the installation program, be aware of two issues:
  • Once the boot: prompt appears, the installation program automatically begins if you take no action within the first minute. To disable this feature, press one of the help screen function keys.
  • If you press a help screen function key, there is a slight delay while the help screen is read from the boot media.
Normally, you only need to press Enter to boot. Be sure to watch the boot messages to review if the Linux kernel detects your hardware. If your hardware is properly detected, continue to the next section. If it does not properly detect your hardware, you may need to restart the installation and use one of the boot options provided in Chapter 8, Additional Boot Options for Intel® and AMD Systems.

4.4.2. Booting the Installation Program on Itanium Systems

Your Itanium system should be able to boot the Red Hat Enterprise Linux installation program directly from the Red Hat Enterprise Linux CD #1. If your Itanium cannot boot the installation program from the CD-ROM (or if you want to perform a hard drive, NFS, FTP, or HTTP installation) you must boot from an LS-120 diskette. Refer to Section 4.4.2.2, “Booting the Installation Program from an LS-120 Diskette” for more information.

4.4.2.1. Booting the Installation Program from the DVD/CD-ROM

To boot from the Red Hat Enterprise Linux CD #1 follow these steps:
  1. Remove all media except Red Hat Enterprise Linux CD #1.
  2. From the Boot Option menu choose EFI Shell.
  3. At the Shell> prompt, change to the file system on the CD-ROM. For example, in the above sample map output, the system partition on the CD-ROM is fs1. To change to the fs1 file system, type fs1: at the prompt.
  4. Type elilo linux to boot into the installation program.
  5. Go to Chapter 4, Installing on Intel® and AMD Systems to begin the installation.

4.4.2.2. Booting the Installation Program from an LS-120 Diskette

If your Itanium cannot boot from Red Hat Enterprise Linux CD #1, you must boot from an LS-120 diskette. If you want to perform a hard drive, NFS, FTP, or HTTP installation, you must boot from a boot LS-120 diskette.
You must create an LS-120 boot image file diskette from the boot image file on CD #1: images/boot.img. To create this diskette in Linux, insert a blank LS-120 diskette and type the following command at a shell prompt:
dd if=boot.img of=/dev/hda bs=180k
Replace boot.img with the full path to the boot image file and /dev/hda with the correct device name for the LS-120 diskette drive.
If you are not using the Red Hat Enterprise Linux CD, the installation program starts in text mode and you must choose a few basic options for your system.
If you are using the CD-ROM to load the installation program, follow the instructions contained in Chapter 4, Installing on Intel® and AMD Systems.
To boot from an LS-120 diskette follow these steps:
  1. Insert the LS-120 diskette you made from the boot image file boot.img. If you are performing a local CD-ROM installation but booting off the LS-120 diskette, insert the Red Hat Enterprise Linux CD #1 also. If you are performing a hard drive, NFS, FTP, or HTTP installation, you do not need the CD-ROM.
  2. From the Boot Option menu choose EFI Shell.
  3. At the Shell> prompt, change the device to the LS-120 drive by typing the command fs0:, using the example map output above.
  4. Type elilo linux to boot into the installation program.
  5. Go to Chapter 4, Installing on Intel® and AMD Systems to begin the installation.

4.4.3. Additional Boot Options

While it is easiest to boot using a CD-ROM and perform a graphical installation, sometimes there are installation scenarios where booting in a different manner may be needed. This section discusses additional boot options available for Red Hat Enterprise Linux.
For Itanium users:
To pass options to the boot loader on an Itanium system, enter the following at the EFI Shell prompt:
elilo linux option
For x86, AMD64, and Intel® 64 users:
To pass options to the boot loader on an x86, AMD64, or Intel® 64 system, use the instructions as provided in the boot loader option samples below.

Note

Refer to Chapter 8, Additional Boot Options for Intel® and AMD Systems for additional boot options not covered in this section.
  • To perform a text mode installation, at the installation boot prompt, type:
    linux text
  • ISO images have an md5sum embedded in them. To test the checksum integrity of an ISO image, at the installation boot prompt, type:
    linux mediacheck
    The installation program prompts you to insert a CD or select an ISO image to test, and select OK to perform the checksum operation. This checksum operation can be performed on any Red Hat Enterprise Linux CD and does not have to be performed in a specific order (for example, CD #1 does not have to be the first CD you verify). It is strongly recommended to perform this operation on any Red Hat Enterprise Linux CD that was created from downloaded ISO images. This command works with the CD, DVD, hard drive ISO, and NFS ISO installation methods.
  • Also in the images/ directory is the boot.iso file. This file is an ISO image than can be used to boot the installation program. To use the boot.iso, your computer must be able to boot from its CD-ROM drive, and its BIOS settings must be configured to do so. You must then burn the boot.iso file onto a recordable/rewriteable CD-ROM.
  • If you need to perform the installation in serial mode, type the following command:
    linux console=<device>
    For text mode installations, use:
    linux text console=<device>
    In the above command, <device> should be the device you are using (such as ttyS0 or ttyS1). For example, linux text console=ttyS0.
    Text mode installations using a serial terminal work best when the terminal supports UTF-8. Under UNIX and Linux, Kermit supports UTF-8. For Windows, Kermit '95 works well. Non-UTF-8 capable terminals works as long as only English is used during the installation process. An enhanced serial display can be used by passing the utf8 command as a boot-time option to the installation program. For example:
    linux console=ttyS0 utf8

4.4.3.1. Kernel Options

Options can also be passed to the kernel. For example, to apply updates for the anaconda installation program from a floppy disk enter:
linux updates
For text mode installations, use:
linux text updates
This command will prompt you to insert a floppy diskette containing updates for anaconda. It is not needed if you are performing a network installation and have already placed the updates image contents in rhupdates/ on the server.
After entering any options, press Enter to boot using those options.
If you need to specify boot options to identify your hardware, please write them down. The boot options are needed during the boot loader configuration portion of the installation (refer to Section 4.20, “x86, AMD64, and Intel® 64 Boot Loader Configuration” for more information).
For more information on kernel options refer to Chapter 8, Additional Boot Options for Intel® and AMD Systems.

4.5. Selecting an Installation Method

What type of installation method do you wish to use? The following installation methods are available:
DVD/CD-ROM
If you have a DVD/CD-ROM drive and the Red Hat Enterprise Linux CD-ROMs or DVD you can use this method. Refer to Section 4.6, “Installing from DVD/CD-ROM”, for DVD/CD-ROM installation instructions.
Hard Drive
If you have copied the Red Hat Enterprise Linux ISO images to a local hard drive, you can use this method. You need a boot CD-ROM (use the linux askmethod boot option). Refer to Section 4.7, “Installing from a Hard Drive”, for hard drive installation instructions.
NFS
If you are installing from an NFS server using ISO images or a mirror image of Red Hat Enterprise Linux, you can use this method. You need a boot CD-ROM (use the linux askmethod boot option). Refer to Section 4.9, “Installing via NFS” for network installation instructions. Note that NFS installations may also be performed in GUI mode.
FTP
If you are installing directly from an FTP server, use this method. You need a boot CD-ROM (use the linux askmethod boot option). Refer to Section 4.10, “Installing via FTP”, for FTP installation instructions.
HTTP
If you are installing directly from an HTTP (Web) server, use this method. You need a boot CD-ROM (use the linux askmethod boot option). Refer to Section 4.11, “Installing via HTTP”, for HTTP installation instructions.

4.6. Installing from DVD/CD-ROM

To install Red Hat Enterprise Linux from a DVD/CD-ROM, place the DVD or CD #1 in your DVD/CD-ROM drive and boot your system from the DVD/CD-ROM.
The installation program then probes your system and attempts to identify your CD-ROM drive. It starts by looking for an IDE (also known as an ATAPI) CD-ROM drive.

Note

To abort the installation process at this time, reboot your machine and then eject the boot media. You can safely cancel the installation at any point before the About to Install screen. Refer to Section 4.25, “Preparing to Install” for more information.
If your CD-ROM drive is not detected, and it is a SCSI CD-ROM, the installation program prompts you to choose a SCSI driver. Choose the driver that most closely resembles your adapter. You may specify options for the driver if necessary; however, most drivers detect your SCSI adapter automatically.
If the DVD/CD-ROM drive is found and the driver loaded, the installer will present you with the option to perform a media check on the DVD/CD-ROM. This will take some time, and you may opt to skip over this step. However, if you later encounter problems with the installer, you should reboot and perform the media check before calling for support. From the media check dialog, continue to the next stage of the installation process (refer to Section 4.12, “Welcome to Red Hat Enterprise Linux”).

4.7. Installing from a Hard Drive

The Select Partition screen applies only if you are installing from a disk partition (that is, if you used the askmethod boot options and selected Hard Drive in the Installation Method dialog). This dialog allows you to name the disk partition and directory from which you are installing Red Hat Enterprise Linux. If you used the repo=hd boot option, you already specified a partition.
Selecting Partition Dialog for Hard Drive Installation

Figure 4.3. Selecting Partition Dialog for Hard Drive Installation

Enter the device name of the partition containing the Red Hat Enterprise Linux ISO images. This partition must be formatted with a ext2 or vfat filesystem, and cannot be a logical volume. There is also a field labeled Directory holding images.
If the ISO images are in the root (top-level) directory of a partition, enter a /. If the ISO images are located in a subdirectory of a mounted partition, enter the name of the directory holding the ISO images within that partition. For example, if the partition on which the ISO images is normally mounted as /home/, and the images are in /home/new/, you would enter /new/.
After you have identified the disk partition, the Welcome dialog appears.

4.8. Performing a Network Installation

If you are performing a network installation and booted with the askmethod boot option, the Configure TCP/IP dialog appears. This dialog asks for your IP and other network addresses. You can choose to configure the IP address and Netmask of the device via DHCP or manually. If manually, you have the option to enter IPv4 and/or IPv6 information. Enter the IP address you are using during installation and press Enter. Note that you need to supply IPv4 information if you wish to perform an NFS installation.
TCP/IP Configuration

Figure 4.4. TCP/IP Configuration

4.9. Installing via NFS

The NFS dialog applies only if you are installing from an NFS server (if you selected NFS Image in the Installation Method dialog).
Enter the domain name or IP address of your NFS server. For example, if you are installing from a host named eastcoast in the domain example.com, enter eastcoast.example.com in the NFS Server field.
Next, enter the name of the exported directory. If you followed the setup described in Section 2.5, “Preparing for a Network Installation”, you would enter the directory /export/directory/.
If the NFS server is exporting a mirror of the Red Hat Enterprise Linux installation tree, enter the directory which contains the root of the installation tree. You will enter an Installation Key later on in the process which will determine which subdirectories are used to install from. If everything was specified properly, a message appears indicating that the installation program for Red Hat Enterprise Linux is running.
NFS Setup Dialog

Figure 4.5. NFS Setup Dialog

If the NFS server is exporting the ISO images of the Red Hat Enterprise Linux CD-ROMs, enter the directory which contains the ISO images.
Next, the Welcome dialog appears.

4.10. Installing via FTP

The FTP dialog applies only if you are installing from an FTP server (that is, if you used the askmethod boot options and selected FTP in the Installation Method dialog). This dialog allows you to identify the FTP server from which you are installing Red Hat Enterprise Linux. If you used the repo=ftp boot option, you already specified a server and path.
FTP Setup Dialog

Figure 4.6. FTP Setup Dialog

Enter the name or IP address of the FTP site you are installing from, and the name of the directory containing the variant/ directory for your architecture. For example, if the FTP site contains the directory /mirrors/redhat/arch/variant;/, enter /mirrors/redhat/arch/ (where arch is replaced with the architecture type of your system, such as i386, ia64, ppc, or s390x, and variant is the variant that you are installing, such as Client, Server, Workstation, etc.). If everything was specified properly, a message box appears indicating that files are being retrieved from the server.
Next, the Welcome dialog appears.

Note

You can save disk space by using the ISO images you have already copied to the server. To accomplish this, install Red Hat Enterprise Linux using ISO images without copying them into a single tree by loopback mounting them. For each ISO image:
mkdir discX
mount -o loop RHEL5-discX.iso discX
Replace X with the corresponding disc number.

4.11. Installing via HTTP

The HTTP dialog applies only if you are installing from an HTTP server (that is, if you used the askmethod boot option and selected HTTP in the Installation Method dialog). This dialog prompts you for information about the HTTP server from which you are installing Red Hat Enterprise Linux. If you used the repo=http boot option, you already specified a server and path.
Enter the name or IP address of the HTTP site you are installing from, and the name of the directory containing the variant/ directory for your architecture. For example, if the HTTP site contains the directory /mirrors/redhat/arch/variant/, enter /mirrors/redhat/arch/ (where arch is replaced with the architecture type of your system, such as i386, ia64, ppc, or s390x, and variant is the variant that you are installing, such as Client, Server, Workstation, etc.). If everything was specified properly, a message box appears indicating that files are being retrieved from the server.
HTTP Setup Dialog

Figure 4.7. HTTP Setup Dialog

Next, the Welcome dialog appears.

Note

You can save disk space by using the ISO images you have already copied to the server. To accomplish this, install Red Hat Enterprise Linux using ISO images without copying them into a single tree by loopback mounting them. For each ISO image:
mkdir discX
mount -o loop RHEL5-discX.iso discX
Replace X with the corresponding disc number.

4.12. Welcome to Red Hat Enterprise Linux

The Welcome screen does not prompt you for any input. From this screen you can access the Release Notes for Red Hat Enterprise Linux 5.11 by clicking on the Release Notes button.
Click on the Next button to continue.

4.13. Language Selection

Using your mouse, select a language to use for the installation (refer to Figure 4.8, “Language Selection”).
The language you select here will become the default language for the operating system once it is installed. Selecting the appropriate language also helps target your time zone configuration later in the installation. The installation program tries to define the appropriate time zone based on what you specify on this screen.
Language Selection

Figure 4.8. Language Selection

Once you select the appropriate language, click Next to continue.

4.14. Keyboard Configuration

Using your mouse, select the correct layout type (for example, U.S. English) for the keyboard you would prefer to use for the installation and as the system default (refer to the figure below).
Once you have made your selection, click Next to continue.
Keyboard Configuration

Figure 4.9. Keyboard Configuration

Note

To change your keyboard layout type after you have completed the installation, use the Keyboard Configuration Tool.
Type the system-config-keyboard command in a shell prompt to launch the Keyboard Configuration Tool. If you are not root, it prompts you for the root password to continue.

4.15. Enter the Installation Number

Enter your Installation Number (refer to Figure 4.10, “Installation Number”). This number will determine the package selection set that is available to the installer. If you choose to skip entering the installation number you will be presented with a basic selection of packages to install later on.
Installation Number

Figure 4.10. Installation Number

4.16. Disk Partitioning Setup

Partitioning allows you to divide your hard drive into isolated sections, where each section behaves as its own hard drive. Partitioning is particularly useful if you run multiple operating systems. If you are not sure how you want your system to be partitioned, read Chapter 26, An Introduction to Disk Partitions for more information.
On this screen you can choose to create the default layout or choose to manual partition using the 'Create custom layout' option of Disk Druid.
The first three options allow you to perform an automated installation without having to partition your drive(s) yourself. If you do not feel comfortable with partitioning your system, it is recommended that you do not choose to create a custom layout and instead let the installation program partition for you.
You can configure an iSCSI target for installation, or disable a dmraid device from this screen by clicking on the 'Advanced storage configuration' button. For more information refer to Section 4.17, “ Advanced Storage Options ”.

Warning

The Update Agent downloads updated packages to /var/cache/yum/ by default. If you partition the system manually, and create a separate /var/ partition, be sure to create the partition large enough (3.0 GB or more) to download package updates.
Disk Partitioning Setup

Figure 4.11. Disk Partitioning Setup

If you choose to create a custom layout using Disk Druid, refer to Section 4.19, “Partitioning Your System”.

Warning

If you receive an error after the Disk Partitioning Setup phase of the installation saying something similar to:
"The partition table on device hda was unreadable. To create new partitions it must be initialized, causing the loss of ALL DATA on this drive."
you may not have a partition table on that drive or the partition table on the drive may not be recognizable by the partitioning software used in the installation program.
Users who have used programs such as EZ-BIOS have experienced similar problems, causing data to be lost (assuming the data was not backed up before the installation began).
No matter what type of installation you are performing, backups of the existing data on your systems should always be made.

Important

To install Red Hat Enterprise Linux on a network device accessible through multiple paths, deselect all local storage in the Select the drive(s) to use for this installation window, and select a device labeled mapper/mpath instead.
Note that migrating the root file system of an existing Red Hat Enterprise Linux installation from single path storage to multipath storage is not supported. You must perform a new installation to move the root file system to a multipath storage device. Therefore you should plan your installation accordingly. See https://access.redhat.com/site/solutions/66501 for more information.

4.17.  Advanced Storage Options

Advanced Storage Options

Figure 4.12. Advanced Storage Options

From this screen you can choose to disable a dmraid device, in which case the individual elements of the dmraid device will appear as separate hard drives. You can also choose to configure an iSCSI (SCSI over TCP/IP) target.
To configure an ISCSI target invoke the Configure ISCSI Parameters dialog by selecting Add ISCSI target and clicking on the Add Drive button. If a network connection is not already active, the installer prompts you to provide details of your network interface. Select your network interface from the drop-down menu, then either leave the Use dynamic IP configuration box checked, or uncheck it to enter the IP address of your system and the IP addresses of the gateway and nameserver on your network. Ensure that the Enable IPv4 box remains checked.
Enable network Interface

Figure 4.13. Enable network Interface

Fill in the details for the iSCSI target IP and provide a unique iSCSI initiator name to identify this system. If the iSCSI target uses Challenge Handshake Authentication Protocol (CHAP) for authentication, enter the CHAP username and password. If your environment uses 2-way CHAP (also called "Mutual CHAP"), also enter the reverse CHAP username and password. Click the Add target button to attempt connection to the ISCSI target using this information.
Configure ISCSI Parameters

Figure 4.14. Configure ISCSI Parameters

Please note that you will be able to reattempt with a different ISCSI target IP should you enter it incorrectly, but in order to change the ISCSI initiator name you will need to restart the installation.

4.18. Create Default Layout

Create default layout allows you to have some control concerning what data is removed (if any) from your system. Your options are:
  • Remove all partitions on selected drives and create default layout — select this option to remove all partitions on your hard drive(s) (this includes partitions created by other operating systems such as Windows VFAT or NTFS partitions).

    Warning

    If you select this option, all data on the selected hard drive(s) is removed by the installation program. Do not select this option if you have information that you want to keep on the hard drive(s) where you are installing Red Hat Enterprise Linux.
  • Remove Linux partitions on selected drives and create default layout — select this option to remove only Linux partitions (partitions created from a previous Linux installation). This does not remove other partitions you may have on your hard drive(s) (such as VFAT or FAT32 partitions).
  • Use free space on selected drives and create default layout — select this option to retain your current data and partitions, assuming you have enough free space available on your hard drive(s).
Create Default Layout

Figure 4.15. Create Default Layout

Using your mouse, choose the storage drive(s) on which you want Red Hat Enterprise Linux to be installed. If you have two or more drives, you can choose which drive(s) should contain this installation. Unselected drives, and any data on them, are not touched.

Warning

It is always a good idea to back up any data that you have on your systems. For example, if you are upgrading or creating a dual-boot system, you should back up any data you wish to keep on your drive(s). Mistakes do happen and can result in the loss of all your data.

Note

If you have a RAID card, be aware that some BIOSes do not support booting from the RAID card. In cases such as these, the /boot/ partition must be created on a partition outside of the RAID array, such as on a separate hard drive. An internal hard drive is necessary to use for partition creation with problematic RAID cards.
A /boot/ partition is also necessary for software RAID setups.
If you have chosen to automatically partition your system, you should select Review and manually edit your /boot/ partition.
To review and make any necessary changes to the partitions created by automatic partitioning, select the Review option. After selecting Review and clicking Next to move forward, the partitions created for you in Disk Druid appear. You can make modifications to these partitions if they do not meet your needs.
Click Next once you have made your selections to proceed.

4.19. Partitioning Your System

If you chose one of the three automatic partitioning options and did not select Review, skip ahead to Section 4.21, “Network Configuration”.
If you chose one of the automatic partitioning options and selected Review, you can either accept the current partition settings (click Next), or modify the setup using Disk Druid, the manual partitioning tool.

Note

Please note that in the text mode installation it is not possible to work with LVM (Logical Volumes) beyond viewing the existing setup. LVM can only be set up using the graphical Disk Druid program in a graphical installation.
If you chose to create a custom layout, you must tell the installation program where to install Red Hat Enterprise Linux. This is done by defining mount points for one or more disk partitions in which Red Hat Enterprise Linux is installed. You may also need to create and/or delete partitions at this time.

Note

If you have not yet planned how to set up your partitions, refer to Chapter 26, An Introduction to Disk Partitions and Section 4.19.4, “Recommended Partitioning Scheme”. At a bare minimum, you need an appropriately-sized root partition, and a swap partition equal to twice the amount of RAM you have on the system. Itanium system users should have a /boot/efi/ partition of approximately 100 MB and of type FAT (VFAT), a swap partition of at least 512 MB, and an appropriately-sized root (/) partition.
Partitioning with Disk Druid on x86, AMD64, and Intel 64 Systems

Figure 4.16. Partitioning with Disk Druid on x86, AMD64, and Intel® 64 Systems

The partitioning tool used by the installation program is Disk Druid. With the exception of certain esoteric situations, Disk Druid can handle the partitioning requirements for a typical installation.

4.19.1. Graphical Display of Hard Drive(s)

Disk Druid offers a graphical representation of your hard drive(s).
Using your mouse, click once to highlight a particular field in the graphical display. Double-click to edit an existing partition or to create a partition out of existing free space.
Above the display, you can review the name of the drive (such as /dev/hda), its size (in MB), and its model as detected by the installation program.

4.19.2. Disk Druid's Buttons

These buttons control Disk Druid's actions. They are used to change the attributes of a partition (for example the file system type and mount point) and also to create RAID devices. Buttons on this screen are also used to accept the changes you have made, or to exit Disk Druid. For further explanation, take a look at each button in order:
  • New: Used to request a new partition. When selected, a dialog box appears containing fields (such as the mount point and size fields) that must be filled in.
  • Edit: Used to modify attributes of the partition currently selected in the Partitions section. Selecting Edit opens a dialog box. Some or all of the fields can be edited, depending on whether the partition information has already been written to disk.
    You can also edit free space as represented in the graphical display to create a new partition within that space. Either highlight the free space and then select the Edit button, or double-click on the free space to edit it.
  • To make a RAID device, you must first create (or reuse existing) software RAID partitions. Once you have created two or more software RAID partitions, select Make RAID to join the software RAID partitions into a RAID device.
  • Delete: Used to remove the partition currently highlighted in the Current Disk Partitions section. You will be asked to confirm the deletion of any partition.
  • Reset: Used to restore Disk Druid to its original state. All changes made will be lost if you Reset the partitions.
  • RAID: Used to provide redundancy to any or all disk partitions. It should only be used if you have experience using RAID. To read more about RAID, see the Red Hat Enterprise Linux Deployment Guide.
    To make a RAID device, you must first create software RAID partitions. Once you have created two or more software RAID partitions, select RAID to join the software RAID partitions into a RAID device.
  • LVM: Allows you to create an LVM logical volume. The role of LVM (Logical Volume Manager) is to present a simple logical view of underlying physical storage space, such as a hard drive(s). LVM manages individual physical disks — or to be more precise, the individual partitions present on them. It should only be used if you have experience using LVM. To read more about LVM, see the Red Hat Enterprise Linux Deployment Guide. Note, LVM is only available in the graphical installation program.
    To create an LVM logical volume, you must first create partitions of type physical volume (LVM). Once you have created one or more physical volume (LVM) partitions, select LVM to create an LVM logical volume.

4.19.3. Partition Fields

Above the partition hierarchy are labels which present information about the partitions you are creating. The labels are defined as follows:
  • Device: This field displays the partition's device name.
  • Mount Point/RAID/Volume: A mount point is the location within the directory hierarchy at which a volume exists; the volume is "mounted" at this location. This field indicates where the partition is mounted. If a partition exists, but is not set, then you need to define its mount point. Double-click on the partition or click the Edit button.
  • Type: This field shows the partition's file system type (for example, ext2, ext3, or vfat).
  • Format: This field shows if the partition being created will be formatted.
  • Size (MB): This field shows the partition's size (in MB).
  • Start: This field shows the cylinder on your hard drive where the partition begins.
  • End: This field shows the cylinder on your hard drive where the partition ends.
Hide RAID device/LVM Volume Group members: Select this option if you do not want to view any RAID device or LVM Volume Group members that have been created.

4.19.4. Recommended Partitioning Scheme

4.19.4.1. Itanium systems

Unless you have a reason for doing otherwise, we recommend that you create the following partitions for Itanium systems:
  • A /boot/efi/ partition (100 MB minimum) — the partition mounted on /boot/efi/ contains all the installed kernels, the initrd images, and ELILO configuration files.

    Warning

    You must create a /boot/efi/ partition of type VFAT and at least 100 MB in size as the first primary partition.
  • A swap partition (at least 256 MB) — swap partitions are used to support virtual memory. In other words, data is written to a swap partition when there is not enough RAM to store the data your system is processing.
    In years past, the recommended amount of swap space increased linearly with the amount of RAM in the system. But because the amount of memory in modern systems has increased into the hundreds of gigabytes, it is now recognized that the amount of swap space that a system needs is a function of the memory workload running on that system. However, given that swap space is usually designated at install time, and that it can be difficult to determine beforehand the memory workload of a system, we recommend determining system swap using the following table.

    Table 4.2. Recommended System Swap Space

    Amount of RAM in the System Recommended Amount of Swap Space
    4GB of RAM or less a minimum of 2GB of swap space
    4GB to 16GB of RAM a minimum of 4GB of swap space
    16GB to 64GB of RAM a minimum of 8GB of swap space
    64GB to 256GB of RAM a minimum of 16GB of swap space
    256GB to 512GB of RAM a minimum of 32GB of swap space
    Note that you can obtain better performance by distributing swap space over multiple storage devices, particularly on systems with fast drives, controllers, and interfaces.
  • A root partition (3.0 GB - 5.0 GB) — this is where "/" (the root directory) is located. In this setup, all files (except those stored in /boot/efi) are on the root partition.
    A 3.0 GB partition allows you to install a minimal installation, while a 5.0 GB root partition lets you perform a full installation, choosing all package groups.

4.19.4.2. x86, AMD64, and Intel® 64 systems

Unless you have a reason for doing otherwise, we recommend that you create the following partitions for x86, AMD64, and Intel® 64 systems:
  • A swap partition (at least 256 MB) — swap partitions are used to support virtual memory. In other words, data is written to a swap partition when there is not enough RAM to store the data your system is processing.
    In years past, the recommended amount of swap space increased linearly with the amount of RAM in the system. But because the amount of memory in modern systems has increased into the hundreds of gigabytes, it is now recognized that the amount of swap space that a system needs is a function of the memory workload running on that system. However, given that swap space is usually designated at install time, and that it can be difficult to determine beforehand the memory workload of a system, we recommend determining system swap using the following table.

    Table 4.3. Recommended System Swap Space

    Amount of RAM in the System Recommended Amount of Swap Space
    4GB of RAM or less a minimum of 2GB of swap space
    4GB to 16GB of RAM a minimum of 4GB of swap space
    16GB to 64GB of RAM a minimum of 8GB of swap space
    64GB to 256GB of RAM a minimum of 16GB of swap space
    256GB to 512GB of RAM a minimum of 32GB of swap space
    Note that you can obtain better performance by distributing swap space over multiple storage devices, particularly on systems with fast drives, controllers, and interfaces.
  • A /boot/ partition (250 MB) — the partition mounted on /boot/ contains the operating system kernel (which allows your system to boot Red Hat Enterprise Linux), along with files used during the bootstrap process. Due to limitations, creating a native ext3 partition to hold these files is required. For most users, a 250 MB boot partition is sufficient.

    Note

    If your hard drive is more than 1024 cylinders (and your system was manufactured more than two years ago), you may need to create a /boot/ partition if you want the / (root) partition to use all of the remaining space on your hard drive.

    Note

    If you have a RAID card, be aware that some BIOSes do not support booting from the RAID card. In cases such as these, the /boot/ partition must be created on a partition outside of the RAID array, such as on a separate hard drive.
  • A root partition (3.0 GB - 5.0 GB) — this is where "/" (the root directory) is located. In this setup, all files (except those stored in /boot) are on the root partition.
    A 3.0 GB partition allows you to install a minimal installation, while a 5.0 GB root partition lets you perform a full installation, choosing all package groups.
  • A home partition (at least 100 MB) — for storing user data separately from system data. This will be a dedicated partition within a volume group for the /home directory. This will enable you to upgrade or reinstall Red Hat Enterprise Linux without erasing user data files.

Warning

Red Hat Enterprise Linux 5.11 does not support having a separate /var on a network filesystem (for example, NFS, iSCSI, or NBD) The /var directory contains critical data that must be read from or written to during the boot process before establishing network services.
However, you may have /var/spool, /var/www or other subdirectories on a separate network disk, just not the complete /var filesystem.

4.19.5. Adding Partitions

To add a new partition, select the New button. A dialog box appears (refer to Figure 4.17, “Creating a New Partition”).

Note

You must dedicate at least one partition for this installation, and optionally more. For more information, refer to Chapter 26, An Introduction to Disk Partitions.
Creating a New Partition

Figure 4.17. Creating a New Partition

  • Mount Point: Enter the partition's mount point. For example, if this partition should be the root partition, enter /; enter /boot for the /boot partition, and so on. You can also use the pull-down menu to choose the correct mount point for your partition. For a swap partition the mount point should not be set - setting the filesystem type to swap is sufficient.
  • File System Type: Using the pull-down menu, select the appropriate file system type for this partition. For more information on file system types, refer to Section 4.19.5.1, “File System Types”.
  • Allowable Drives: This field contains a list of the hard disks installed on your system. If a hard disk's box is highlighted, then a desired partition can be created on that hard disk. If the box is not checked, then the partition will never be created on that hard disk. By using different checkbox settings, you can have Disk Druid place partitions where you need them, or let Disk Druid decide where partitions should go.
  • Size (MB): Enter the size (in megabytes) of the partition. Note, this field starts with 100 MB; unless changed, only a 100 MB partition will be created.
  • Additional Size Options: Choose whether to keep this partition at a fixed size, to allow it to "grow" (fill up the available hard drive space) to a certain point, or to allow it to grow to fill any remaining hard drive space available.
    If you choose Fill all space up to (MB), you must give size constraints in the field to the right of this option. This allows you to keep a certain amount of space free on your hard drive for future use.
  • Force to be a primary partition: Select whether the partition you are creating should be one of the first four partitions on the hard drive. If unselected, the partition is created as a logical partition. Refer to Section 26.1.3, “Partitions within Partitions — An Overview of Extended Partitions”, for more information.
  • Encrypt: Choose whether to encrypt the partition so that the data stored on it cannot be accessed without a passphrase, even if the storage device is connected to another system. Refer to Chapter 29, Disk Encryption Guide for information on encryption of storage devices. If you select this option, the installer prompts you to provide a passphrase before it writes the partition to the disk.
  • OK: Select OK once you are satisfied with the settings and wish to create the partition.
  • Cancel: Select Cancel if you do not want to create the partition.

4.19.5.1. File System Types

Red Hat Enterprise Linux allows you to create different partition types, based on the file system they will use. The following is a brief description of the different file systems available, and how they can be utilized.
  • ext3 — The ext3 file system is based on the ext2 file system and has one main advantage — journaling. Using a journaling file system reduces time spent recovering a file system after a crash as there is no need to fsck [2] the file system. A maximum file system size of 16TB is supported for ext3. The ext3 file system is selected by default and is highly recommended.
  • ext2 — An ext2 file system supports standard Unix file types (regular files, directories, symbolic links, etc). It provides the ability to assign long file names, up to 255 characters.
  • physical volume (LVM) — Creating one or more physical volume (LVM) partitions allows you to create an LVM logical volume. LVM can improve performance when using physical disks. For more information regarding LVM, see the Red Hat Enterprise Linux Deployment Guide.
  • software RAID — Creating two or more software RAID partitions allows you to create a RAID device. For more information regarding RAID, see chapter RAID (Redundant Array of Independent Disks) in the Red Hat Enterprise Linux Deployment Guide.
  • swap — Swap partitions are used to support virtual memory. In other words, data is written to a swap partition when there is not enough RAM to store the data your system is processing. See the Red Hat Enterprise Linux Deployment Guide for additional information.
  • vfat — The VFAT file system is a Linux file system that is compatible with Microsoft Windows long filenames on the FAT file system. This file system must be used for the /boot/efi/ partition on Itanium systems.

4.19.6. Editing Partitions

To edit a partition, select the Edit button or double-click on the existing partition.

Note

If the partition already exists on your disk, you can only change the partition's mount point. To make any other changes, you must delete the partition and recreate it.

4.19.7. Deleting a Partition

To delete a partition, highlight it in the Partitions section and click the Delete button. Confirm the deletion when prompted.
For further installation instructions for x86, AMD64, and Intel® 64 systems, skip to Section 4.20, “x86, AMD64, and Intel® 64 Boot Loader Configuration”.
For further installation instructions for Itanium systems, skip to Section 4.21, “Network Configuration”.

4.20. x86, AMD64, and Intel® 64 Boot Loader Configuration

To boot the system without boot media, you usually need to install a boot loader. A boot loader is the first software program that runs when a computer starts. It is responsible for loading and transferring control to the operating system kernel software. The kernel, in turn, initializes the rest of the operating system.
GRUB (GRand Unified Bootloader), which is installed by default, is a very powerful boot loader. GRUB can load a variety of free operating systems, as well as proprietary operating systems with chain-loading (the mechanism for loading unsupported operating systems, such as DOS or Windows, by loading another boot loader).
Boot Loader Configuration

Figure 4.18. Boot Loader Configuration

If you do not want to install GRUB as your boot loader, click Change boot loader, where you can choose not to install a boot loader at all.
If you already have a boot loader that can boot Red Hat Enterprise Linux and do not want to overwrite your current boot loader, choose Do not install a boot loader by clicking on the Change boot loader button.

Warning

If you choose not to install GRUB for any reason, you will not be able to boot the system directly, and you must use another boot method (such as a commercial boot loader application). Use this option only if you are sure you have another way of booting the system!
Every bootable partition is listed, including partitions used by other operating systems. The partition holding the system's root file system has a Label of Red Hat Enterprise Linux (for GRUB). Other partitions may also have boot labels. To add or change the boot label for other partitions that have been detected by the installation program, click once on the partition to select it. Once selected, you can change the boot label by clicking the Edit button.
Select Default beside the preferred boot partition to choose your default bootable OS. You cannot move forward in the installation unless you choose a default boot image.

Note

The Label column lists what you must enter at the boot prompt, in non-graphical boot loaders, in order to boot the desired operating system.
Once you have loaded the GRUB boot screen, use the arrow keys to choose a boot label or type e for edit. You are presented with a list of items in the configuration file for the boot label you have selected.
Boot loader passwords provide a security mechanism in an environment where physical access to your server is available.
If you are installing a boot loader, you should create a password to protect your system. Without a boot loader password, users with access to your system can pass options to the kernel which can compromise your system security. With a boot loader password in place, the password must first be entered before selecting any non-standard boot options. However, it is still possible for someone with physical access to the machine to boot from a diskette, CD-ROM, or USB media if the BIOS supports it. Security plans which include boot loader passwords should also address alternate boot methods.
If you choose to use a boot loader password to enhance your system security, be sure to select the checkbox labeled Use a boot loader password.
Once selected, enter a password and confirm it.

Important

When selecting a GRUB password, be aware that GRUB recognizes only the QWERTY keyboard layout, regardless of the keyboard actually attached to the system. If you use a keyboard with a significantly different layout, it might be more effective to memorize a pattern of keystrokes rather than the word that the pattern produces.
To configure more advanced boot loader options, such as changing the drive order or passing options to the kernel, be sure Configure advanced boot loader options is selected before clicking Next.

Important

If you are installing Red Hat Enterprise Linux on a network device accessible through multiple paths, ensure that you select Configure advanced boot loader options before you click Next.

4.20.1. Advanced Boot Loader Configuration

Now that you have chosen which boot loader to install, you can also determine where you want the boot loader to be installed. You may install the boot loader in one of two places:
  • The master boot record (MBR) — This is the recommended place to install a boot loader, unless the MBR already starts another operating system loader, such as System Commander. The MBR is a special area on your hard drive that is automatically loaded by your computer's BIOS, and is the earliest point at which the boot loader can take control of the boot process. If you install it in the MBR, when your machine boots, GRUB presents a boot prompt. You can then boot Red Hat Enterprise Linux or any other operating system that you have configured the boot loader to boot.
  • The first sector of your boot partition — This is recommended if you are already using another boot loader on your system. In this case, your other boot loader takes control first. You can then configure that boot loader to start GRUB, which then boots Red Hat Enterprise Linux.
Boot Loader Installation

Figure 4.19. Boot Loader Installation

Note

If you have a RAID card, be aware that some BIOSes do not support booting from the RAID card. In cases such as these, the boot loader should not be installed on the MBR of the RAID array. Rather, the boot loader should be installed on the MBR of the same drive as the /boot/ partition was created.
If your system only uses Red Hat Enterprise Linux, you should choose the MBR.
Click the Change Drive Order button if you would like to rearrange the drive order or if your BIOS does not return the correct drive order. Changing the drive order may be useful if you have multiple SCSI adapters, or both SCSI and IDE adapters, and you want to boot from the SCSI device.
The Force LBA32 (not normally required) option allows you to exceed the 1024 cylinder limit for the /boot/ partition. If you have a system which supports the LBA32 extension for booting operating systems above the 1024 cylinder limit, and you want to place your /boot/ partition above cylinder 1024, you should select this option.

Note

While partitioning your hard drive, keep in mind that the BIOS in some older systems cannot access more than the first 1024 cylinders on a hard drive. If this is the case, leave enough room for the /boot Linux partition on the first 1024 cylinders of your hard drive to boot Linux. The other Linux partitions can be after cylinder 1024.
In parted, 1024 cylinders equals 528MB. For more information, refer to:
http://www.pcguide.com/ref/hdd/bios/sizeMB504-c.html
To add default options to the boot command, enter them into the Kernel parameters field. Any options you enter are passed to the Linux kernel every time it boots.

Important

If you are installing Red Hat Enterprise Linux on a network device accessible through multiple paths, ensure that GRUB is installed on the MBR of /dev/mapper/mpath0.

4.20.2. Rescue Mode

Rescue mode provides the ability to boot a small Red Hat Enterprise Linux environment entirely from boot media or some other boot method instead of the system's hard drive. There may be times when you are unable to get Red Hat Enterprise Linux running completely enough to access files on your system's hard drive. Using rescue mode, you can access the files stored on your system's hard drive, even if you cannot actually run Red Hat Enterprise Linux from that hard drive. If you need to use rescue mode, try the following method:
  • Using the CD-ROM to boot an x86, AMD64, or Intel® 64 system, type linux rescue at the installation boot prompt. Itanium users should type elilo linux rescue to enter rescue mode.
For additional information, see the Red Hat Enterprise Linux Deployment Guide.

4.20.3. Alternative Boot Loaders

If you do not wish to use a boot loader, you have several alternatives:
LOADLIN
You can load Linux from MS-DOS. Unfortunately, this requires a copy of the Linux kernel (and an initial RAM disk, if you have a SCSI adapter) to be available on an MS-DOS partition. The only way to accomplish this is to boot your Red Hat Enterprise Linux system using some other method (for example, from a boot CD-ROM) and then copy the kernel to an MS-DOS partition. LOADLIN is available from
and associated mirror sites.
SYSLINUX
SYSLINUX is an MS-DOS program very similar to LOADLIN. It is also available from
and associated mirror sites.
Commercial boot loaders
You can load Linux using commercial boot loaders. For example, System Commander and Partition Magic are able to boot Linux (but still require GRUB to be installed in your Linux root partition).

Note

Boot loaders such as LOADLIN and System Commander are considered to be third-party boot loaders and are not supported by Red Hat.

4.20.4. SMP Motherboards and GRUB

In previous versions of Red Hat Enterprise Linux there were two different kernel versions, a uniprocessor version and an SMP version. In Red Hat Enterprise Linux 5.11 the kernel is SMP-enabled by default and will take advantage of multiple core, hyperthreading, and multiple CPU capabilities when they are present. This same kernel can run on single CPUs with a single core and no hyperthreading.

4.21. Network Configuration

If you do not have a network device, this screen does not appear during your installation and you should advance to Section 4.22, “Time Zone Configuration”.
Network Configuration

Figure 4.20. Network Configuration

The installation program automatically detects any network devices you have and displays them in the Network Devices list.
When you have selected a network device, click Edit. From the Edit Interface dialog, you can choose to configure the IP address and Netmask (for IPv4 - Prefix for IPv6) of the device to use DHCP or to use static settings. If you do not have DHCP client access or you are unsure what to provide here, contact your network administrator.
Editing a Network Device

Figure 4.21. Editing a Network Device

Note

Do not use the numbers as seen in this sample configuration. These values will not work for your own network configuration. If you are not sure what values to enter, contact your network administrator for assistance.
If you have a hostname (fully qualified domain name) for the network device, you can choose to have DHCP (Dynamic Host Configuration Protocol) automatically detect it or you can manually enter the hostname in the field provided.
Finally, if you entered the IP and Netmask information manually, you may also enter the Gateway address and the Primary and Secondary DNS addresses.

Note

Even if your computer is not part of a network, you can enter a hostname for your system. If you do not take this opportunity to enter a name, your system will be known as localhost.

Note

To change your network configuration after you have completed the installation, use the Network Administration Tool.
Type the system-config-network command in a shell prompt to launch the Network Administration Tool. If you are not root, it prompts you for the root password to continue.

4.22. Time Zone Configuration

Set your time zone by selecting the city closest to your computer's physical location. Click on the map to zoom in to a particular geographical region of the world.
From here there are two ways for you to select your time zone:
  • Using your mouse, click on the interactive map to select a specific city (represented by a yellow dot). A red X appears indicating your selection.
  • You can also scroll through the list at the bottom of the screen to select your time zone. Using your mouse, click on a location to highlight your selection.
Configuring the Time Zone

Figure 4.22. Configuring the Time Zone

Select System Clock uses UTC if you know that your system is set to UTC.

Note

To change your time zone configuration after you have completed the installation, use the Time and Date Properties Tool.
Type the system-config-date command in a shell prompt to launch the Time and Date Properties Tool. If you are not root, it prompts you for the root password to continue.
To run the Time and Date Properties Tool as a text-based application, use the command timeconfig.

4.23. Set Root Password

Setting up a root account and password is one of the most important steps during your installation. Your root account is similar to the administrator account used on Windows NT machines. The root account is used to install packages, upgrade RPMs, and perform most system maintenance. Logging in as root gives you complete control over your system.

Note

The root user (also known as the superuser) has complete access to the entire system; for this reason, logging in as the root user is best done only to perform system maintenance or administration.
Root Password

Figure 4.23. Root Password

Use the root account only for system administration. Create a non-root account for your general use and su - to root when you need to fix something quickly. These basic rules minimize the chances of a typo or an incorrect command doing damage to your system.

Note

To become root, type su - at the shell prompt in a terminal window and then press Enter. Then, enter the root password and press Enter.
The installation program prompts you to set a root password[3] for your system. You cannot proceed to the next stage of the installation process without entering a root password.
The root password must be at least six characters long; the password you type is not echoed to the screen. You must enter the password twice; if the two passwords do not match, the installation program asks you to enter them again.
You should make the root password something you can remember, but not something that is easy for someone else to guess. Your name, your phone number, qwerty, password, root, 123456, and anteater are all examples of bad passwords. Good passwords mix numerals with upper and lower case letters and do not contain dictionary words: Aard387vark or 420BMttNT, for example. Remember that the password is case-sensitive. If you write down your password, keep it in a secure place. However, it is recommended that you do not write down this or any password you create.

Note

Do not use one of the example passwords offered in this manual. Using one of these passwords could be considered a security risk.

Note

To change your root password after you have completed the installation, use the Root Password Tool.
Type the system-config-rootpassword command in a shell prompt to launch the Root Password Tool. If you are not root, it prompts you for the root password to continue.

4.24. Package Group Selection

Now that you have made most of the choices for your installation, you are ready to confirm the default package selection or customize packages for your system.
The Package Installation Defaults screen appears and details the default package set for your Red Hat Enterprise Linux installation. This screen varies depending on the version of Red Hat Enterprise Linux you are installing.
If you choose to accept the current package list, skip ahead to Section 4.25, “Preparing to Install”.
To customize your package set further, select the Customize now option on the screen. Clicking Next takes you to the Package Group Selection screen.
You can select package groups, which group components together according to function (for example, X Window System and Editors), individual packages, or a combination of the two.

Note

Users of Itanium systems who want support for developing or running 32-bit applications are encouraged to select the Compatibility Arch Support and Compatibility Arch Development Support packages to install architecture specific support for their systems.
To select a component, click on the checkbox beside it (refer to Figure 4.24, “Package Group Selection”).
Package Group Selection

Figure 4.24. Package Group Selection

Select each component you wish to install.
Once a package group has been selected, if optional components are available you can click on Optional packages to view which packages are installed by default, and to add or remove optional packages from that group. If there are no optional components this button will be disabled.
Package Group Details

Figure 4.25. Package Group Details

4.25. Preparing to Install

4.25.1.  Prepare to Install

A screen preparing you for the installation of Red Hat Enterprise Linux now appears.
For your reference, a complete log of your installation can be found in /root/install.log once you reboot your system.

Warning

If, for some reason, you would rather not continue with the installation process, this is your last opportunity to safely cancel the process and reboot your machine. Once you press the Next button, partitions are written and packages are installed. If you wish to abort the installation, you should reboot now before any existing information on any hard drive is rewritten.
To cancel this installation process, press your computer's Reset button or use the Control+Alt+Delete key combination to restart your machine.

4.26. Installing Packages

At this point there is nothing left for you to do until all the packages have been installed. How quickly this happens depends on the number of packages you have selected and your computer's speed.

4.27. Installation Complete

Congratulations! Your Red Hat Enterprise Linux installation is now complete!
The installation program prompts you to prepare your system for reboot. Remember to remove any installation media if it is not ejected automatically upon reboot.
After your computer's normal power-up sequence has completed, the graphical boot loader prompt appears at which you can do any of the following things:
  • Press Enter — causes the default boot entry to be booted.
  • Select a boot label, followed by Enter — causes the boot loader to boot the operating system corresponding to the boot label.
  • Do nothing — after the boot loader's timeout period, (by default, five seconds) the boot loader automatically boots the default boot entry.
Do whatever is appropriate to boot Red Hat Enterprise Linux. One or more screens of messages should scroll by. Eventually, a login: prompt or a GUI login screen (if you installed the X Window System and chose to start X automatically) appears.
The first time you start your Red Hat Enterprise Linux system in run level 5 (the graphical run level), the Setup Agent is presented, which guides you through the Red Hat Enterprise Linux configuration. Using this tool, you can set your system time and date, install software, register your machine with Red Hat Network, and more. The Setup Agent lets you configure your environment at the beginning, so that you can get started using your Red Hat Enterprise Linux system quickly.
For information on registering your Red Hat Enterprise Linux subscription, refer to Chapter 25, Register Your System and Apply Subscriptions.

4.28. Itanium Systems — Booting Your Machine and Post-Installation Setup

This section describes how to boot your Itanium into Red Hat Enterprise Linux and how to set your EFI console variables so that Red Hat Enterprise Linux is automatically booted when the machine is powered on.
After you reboot your system at the end of the installation program, type the following command to boot into Red Hat Enterprise Linux:
elilo
After you type elilo, the default kernel listed in the /boot/efi/elilo.conf configuration file is loaded. (The first kernel listed in the file is the default.)
If you want to load a different kernel, type the label name of the kernel from the file /boot/efi/elilo.conf after the elilo command. For example, to load the kernel named linux, type:
elilo linux
If you do not know the names of the installed kernels, you can view the /boot/efi/elilo.conf file in EFI with the following instructions:
  1. At the Shell> prompt, change devices to the system partition (mounted as /boot/efi in Linux). For example, if fs0 is the system boot partition, type fs0: at the EFI Shell prompt.
  2. Type ls at the fs0:\> to make sure you are in the correct partition.
  3. Then type:
    Shell>type elilo.conf
    This command displays the contents of the configuration file. Each stanza contains a line beginning with label followed by a label name for that kernel. The label name is what you type after elilo to boot the different kernels.

4.28.1. Post-Installation Boot Loader Options

In addition to specifying a kernel to load, you can also enter other boot options such as single for single user mode or mem=1024M to force Red Hat Enterprise Linux to use 1024 MB of memory. To pass options to the boot loader, enter the following at the EFI Shell prompt (replace linux with the label name of the kernel you want to boot and option with the boot options you want to pass to the kernel):
elilo linux option

4.28.2. Booting Red Hat Enterprise Linux Automatically

After installing Red Hat Enterprise Linux you can type elilo and any boot options at the EFI Shell prompt each time you wish to boot your Itanium system. However, if you wish to configure your system to boot into Red Hat Enterprise Linux automatically, you need to configure the EFI Boot Manager.
To configure the EFI Boot Manager (may vary slightly depending on your hardware):
  1. Boot the Itanium system and choose Boot option maintenance menu from the EFI Boot Manager menu.
  2. Choose Add a Boot Option from the Main Menu.
  3. Select the system partition that is mounted as /boot/efi/ in Linux.
  4. Select the elilo.efi file.
  5. At the Enter New Description: prompt, type Red Hat Enterprise Linux 5, or any name that you want to appear on the EFI Boot Manager menu.
  6. At the Enter Boot Option Data Type: prompt, enter N for No Boot Option if you do not want to pass options to the ELILO boot loader. This option works for most cases. If you want to pass options to the boot loader, you can configure it in the /boot/efi/elilo.conf configuration file instead.
  7. Answer Yes to the Save changes to NVRAM prompt. This returns you to the EFI Boot Maintenance Manager menu.
  8. Next, you want to make the Red Hat Enterprise Linux 5 menu item the default. A list of boot options appears. Move the Red Hat Enterprise Linux 5 menu item up to the top of the list by selecting it with the arrow keys and pressing the u key to move it up the list. You can move items down the list by selecting it and pressing the d key. After changing the boot order, choose Save changes to NVRAM. Choose Exit to return to the Main Menu.
  9. Optionally, you can change the boot timeout value by choosing Set Auto Boot TimeOut => Set Timeout Value from the Main Menu.
  10. Return to the EFI Boot Manager by selecting Exit.

4.28.2.1. Using a Startup Script

It is recommended that you configure the ELILO Boot Manager to boot Red Hat Enterprise Linux automatically. However, if you require additional commands to be executed before starting the ELILO boot loader, you can create a startup script named startup.nsh. The last command should be elilo to boot into Linux.
The startup.nsh script should be in the /boot/efi partition (/boot/efi/startup.nsh) and contain the following text:
echo -off your set of commands elilo
If you want to pass options to the boot loader (refer to Section 4.28.1, “Post-Installation Boot Loader Options”) add them after elilo.
You can either create this file after booting into Red Hat Enterprise Linux or use the editor built into the EFI shell. To use the EFI shell, at the Shell> prompt, change devices to the system partition (mounted as /boot/efi in Linux). For example, if fs0 is the system boot partition, type fs0: at the EFI Shell prompt. Type ls to make sure you are in the correct partition. Then type edit startup.nsh. Type the contents of the file and save it.
The next time the system boots, EFI detects the startup.nsh file and use it to boot the system. To stop EFI from loading the file, type Ctrl+c . This aborts the process, and returns you to the EFI shell prompt.


[2] The fsck application is used to check the file system for metadata consistency and optionally repair one or more Linux file systems.
[3] A root password is the administrative password for your Red Hat Enterprise Linux system. You should only log in as root when needed for system maintenance. The root account does not operate within the restrictions placed on normal user accounts, so changes made as root can have implications for your entire system.

Chapter 5. Removing Red Hat Enterprise Linux

To uninstall Red Hat Enterprise Linux from your x86-based system, you must remove the Red Hat Enterprise Linux boot loader information from your master boot record (MBR).

Note

It is always a good idea to backup any data that you have on your system(s). Mistakes do happen and can result in the loss all of your data.
In DOS and Windows, use the Windows fdisk utility to create a new MBR with the undocumented flag /mbr. This ONLY rewrites the MBR to boot the primary DOS partition. The command should look like the following:
fdisk /mbr
If you need to remove Linux from a hard drive and have attempted to do this with the default DOS (Windows) fdisk, you will experience the Partitions exist but they do not exist problem. The best way to remove non-DOS partitions is with a tool that understands partitions other than DOS.
To begin, insert the Red Hat Enterprise Linux CD #1 and boot your system. Once you have booted off the CD, a boot prompt appears. At the boot prompt, type: linux rescue. This starts the rescue mode program.
You are prompted for your keyboard and language requirements. Enter these values as you would during the installation of Red Hat Enterprise Linux.
Next, a screen appears telling you that the program attempts to find a Red Hat Enterprise Linux install to rescue. Select Skip on this screen.
After selecting Skip, you are given a command prompt where you can access the partitions you would like to remove.
First, type the command list-harddrives. This command lists all hard drives on your system that are recognizable by the installation program, as well as their sizes in megabytes.

Warning

Be careful to remove only the necessary Red Hat Enterprise Linux partitions. Removing other partitions could result in data loss or a corrupted system environment.
To remove partitions, use the partitioning utility parted. Start parted, where /dev/hda is the device on which to remove the partition:
parted /dev/hda
Using the print command, view the current partition table to determine the minor number of the partition to remove:
print
The print command also displays the partition's type (such as linux-swap, ext2, ext3, and so on). Knowing the type of the partition helps you in determining whether to remove the partition.
Remove the partition with the command rm. For example, to remove the partition with minor number 3:
rm 3

Important

The changes start taking place as soon as you press [Enter], so review the command before committing to it.
After removing the partition, use the print command to confirm that it is removed from the partition table.
Once you have removed the Linux partitions and made all of the changes you need to make, type quit to quit parted.
After quitting parted, type exit at the boot prompt to exit rescue mode and reboot your system, instead of continuing with the installation. The system should reboot automatically. If it does not, you can reboot your computer using Control+Alt+Delete .

Chapter 6. Troubleshooting Installation on an Intel® or AMD System

This appendix discusses some common installation problems and their solutions.

6.1. You are Unable to Boot Red Hat Enterprise Linux

6.1.1. Are You Unable to Boot With Your RAID Card?

If you have performed an installation and cannot boot your system properly, you may need to reinstall and create your partitions differently.
Some BIOSes do not support booting from RAID cards. At the end of an installation, a text-based screen showing the boot loader prompt (for example, GRUB: ) and a flashing cursor may be all that appears. If this is the case, you must repartition your system.
Whether you choose automatic or manual partitioning, you must install your /boot partition outside of the RAID array, such as on a separate hard drive. An internal hard drive is necessary to use for partition creation with problematic RAID cards.
You must also install your preferred boot loader (GRUB or LILO) on the MBR of a drive that is outside of the RAID array. This should be the same drive that hosts the /boot/ partition.
Once these changes have been made, you should be able to finish your installation and boot the system properly.

6.1.2. Is Your System Displaying Signal 11 Errors?

A signal 11 error, commonly know as a segmentation fault, means that the program accessed a memory location that was not assigned to it. A signal 11 error may be due to a bug in one of the software programs that is installed, or faulty hardware.
If you receive a fatal signal 11 error during your installation, it is probably due to a hardware error in memory on your system's bus. Like other operating systems, Red Hat Enterprise Linux places its own demands on your system's hardware. Some of this hardware may not be able to meet those demands, even if they work properly under another OS.
Ensure that you have the latest installation updates and images from Red Hat. Review the online errata to see if newer versions are available. If the latest images still fail, it may be due to a problem with your hardware. Commonly, these errors are in your memory or CPU-cache. A possible solution for this error is turning off the CPU-cache in the BIOS, if your system supports this. You could also try to swap your memory around in the motherboard slots to check if the problem is either slot or memory related.
Another option is to perform a media check on your installation CD-ROMs. The Red Hat Enterprise Linux installation program has the ability to test the integrity of the installation media. It works with the CD, DVD, hard drive ISO, and NFS ISO installation methods. Red Hat recommends that you test all installation media before starting the installation process, and before reporting any installation-related bugs (many of the bugs reported are actually due to improperly-burned CDs). To use this test, type the following command at the boot: or yaboot: prompt (prepend with elilo for Itanium systems):
	linux mediacheck
For more information concerning signal 11 errors, refer to:
	http://www.bitwizard.nl/sig11/

6.2. Trouble Beginning the Installation

6.2.1. Problems with Booting into the Graphical Installation

There are some video cards that have trouble booting into the graphical installation program. If the installation program does not run using its default settings, it tries to run in a lower resolution mode. If that still fails, the installation program attempts to run in text mode.
One possible solution is to try using the resolution= boot option. This option may be most helpful for laptop users. Another solution to try is the driver= option to specify the driver that should be loaded for your video card. If this works, it should be reported as a bug as the installer has failed to autodetect your videocard. Refer to Chapter 8, Additional Boot Options for Intel® and AMD Systems for more information on boot options.

Note

To disable frame buffer support and allow the installation program to run in text mode, try using the nofb boot option. This command may be necessary for accessibility with some screen reading hardware.

6.3. Trouble During the Installation

6.3.1. No devices found to install Red Hat Enterprise Linux Error Message

If you receive an error message stating No devices found to install Red Hat Enterprise Linux, there is probably a SCSI controller that is not being recognized by the installation program.
Check your hardware vendor's website to determine if a driver diskette image is available that fixes your problem. For more general information on driver diskettes, refer to Chapter 7, Updating drivers during installation on Intel and AMD systems.
You can also refer to the Red Hat Hardware Compatibility List, available online at:

6.3.2. Saving Traceback Messages Without a Diskette Drive

If you receive a traceback error message during installation, you can usually save it to a diskette.
If you do not have a diskette drive available in your system, you can scp the error message to a remote system.
When the traceback dialog appears, the traceback error message is automatically written to a file named /tmp/anacdump.txt. Once the dialog appears, switch over to a new tty (virtual console) by pressing the keys Ctrl+Alt+F2 and scp the message written to /tmp/anacdump.txt to a known working remote system.

6.3.3. Trouble with Partition Tables

If you receive an error after the Disk Partitioning Setup (Section 4.16, “Disk Partitioning Setup”) phase of the installation saying something similar to
The partition table on device hda was unreadable. To create new partitions it must be initialized, causing the loss of ALL DATA on this drive.
you may not have a partition table on that drive or the partition table on the drive may not be recognizable by the partitioning software used in the installation program.
Users who have used programs such as EZ-BIOS have experienced similar problems, causing data to be lost (assuming the data was not backed up before the installation began) that could not be recovered.
No matter what type of installation you are performing, backups of the existing data on your systems should always be made.

6.3.4. Using Remaining Space

You have a swap and a / (root) partition created, and you have selected the root partition to use the remaining space, but it does not fill the hard drive.
If your hard drive is more than 1024 cylinders, you must create a /boot partition if you want the / (root) partition to use all of the remaining space on your hard drive.

6.3.5. Other Partitioning Problems

If you are using Disk Druid to create partitions, but cannot move to the next screen, you probably have not created all the partitions necessary for Disk Druid's dependencies to be satisfied.
You must have the following partitions as a bare minimum:
  • A / (root) partition
  • A <swap> partition of type swap

Note

When defining a partition's type as swap, do not assign it a mount point. Disk Druid automatically assigns the mount point for you.

6.3.6. Other Partitioning Problems for Itanium System Users

If you are using Disk Druid to create partitions, but cannot move to the next screen, you probably have not created all the partitions necessary for Disk Druid's dependencies to be satisfied.
You must have the following partitions as a bare minimum:
  • A /boot/efi/ partition of type VFAT
  • A / (root) partition
  • A <swap> partition of type swap

Note

When defining a partition's type as swap, you do not have to assign it a mount point. Disk Druid automatically assigns the mount point for you.

6.3.7. Are You Seeing Python Errors?

During some upgrades or installations of Red Hat Enterprise Linux, the installation program (also known as anaconda) may fail with a Python or traceback error. This error may occur after the selection of individual packages or while trying to save the upgrade log in the /tmp/directory. The error may look similar to:
Traceback (innermost last):
File "/var/tmp/anaconda-7.1//usr/lib/anaconda/iw/progress_gui.py", line 20, in run
rc = self.todo.doInstall ()    
File "/var/tmp/anaconda-7.1//usr/lib/anaconda/todo.py", line 1468, in doInstall 
self.fstab.savePartitions ()    
File "fstab.py", line 221, in savePartitions      
sys.exit(0)  
SystemExit: 0   
Local variables in innermost frame:  
self: <fstab.GuiFstab instance at 8446fe0>  
sys: <module 'sys' (built-in)>  
ToDo object:  (itodo  ToDo  p1  (dp2  S'method'  p3  (iimage  CdromInstallMethod  
p4  (dp5  S'progressWindow'  p6   <failed>
This error occurs in some systems where links to /tmp/ are symbolic to other locations or have been changed since creation. These symbolic or changed links are invalid during the installation process, so the installation program cannot write information and fails.
If you experience such an error, first try to download any available errata for anaconda. Errata can be found at:
http://www.redhat.com/support/errata/
The anaconda website may also be a useful reference and can be found online at:
http://fedoraproject.org/wiki/Anaconda
You can also search for bug reports related to this problem. To search Red Hat's bug tracking system, go to:
http://bugzilla.redhat.com/bugzilla/
Finally, if you are still facing problems related to this error, register your product and contact our support team. To register your product, go to:
http://www.redhat.com/apps/activate/

6.4. Problems After Installation

6.4.1. Trouble With the Graphical GRUB Screen on an x86-based System?

If you are experiencing problems with GRUB, you may need to disable the graphical boot screen. To do this, become the root user and edit the /boot/grub/grub.conf file.
Within the grub.conf file, comment out the line which begins with splashimage by inserting the # character at the beginning of the line.
Press Enter to exit the editing mode.
Once the boot loader screen has returned, type b to boot the system.
Once you reboot, the grub.conf file is reread and any changes you have made take effect.
You may re-enable the graphical boot screen by uncommenting (or adding) the above line back into the grub.conf file.

6.4.2. Booting into a Graphical Environment

If you have installed the X Window System but are not seeing a graphical desktop environment once you log into your Red Hat Enterprise Linux system, you can start the X Window System graphical interface using the command startx.
Once you enter this command and press Enter, the graphical desktop environment is displayed.
Note, however, that this is just a one-time fix and does not change the log in process for future log ins.
To set up your system so that you can log in at a graphical login screen, you must edit one file, /etc/inittab, by changing just one number in the runlevel section. When you are finished, reboot the computer. The next time you log in, you are presented with a graphical login prompt.
Open a shell prompt. If you are in your user account, become root by typing the su command.
Now, type gedit /etc/inittab to edit the file with gedit. The file /etc/inittab opens. Within the first screen, a section of the file which looks like the following appears:
# Default runlevel. The runlevels used by RHS are: 
#   0 - halt (Do NOT set initdefault to this) 
#   1 - Single user mode 
#   2 - Multiuser, without NFS (The same as 3, if you do not have networking) 
#   3 - Full multiuser mode 
#   4 - unused 
#   5 - X11 
#   6 - reboot (Do NOT set initdefault to this) 
#  id:3:initdefault:
To change from a console to a graphical login, you should change the number in the line id:3:initdefault: from a 3 to a 5.

Warning

Change only the number of the default runlevel from 3 to 5.
Your changed line should look like the following:
	 id:5:initdefault: 
When you are satisfied with your change, save and exit the file using the Ctrl+Q keys. A window appears and asks if you would like to save the changes. Click Save.
The next time you log in after rebooting your system, you are presented with a graphical login prompt.

6.4.3. Problems with the X Window System (GUI)

If you are having trouble getting X (the X Window System) to start, you may not have installed it during your installation.
If you want X, you can either install the packages from the Red Hat Enterprise Linux CD-ROMs or perform an upgrade.
If you elect to upgrade, select the X Window System packages, and choose GNOME, KDE, or both, during the upgrade package selection process.

6.4.4. Problems with the X Server Crashing and Non-Root Users

If you are having trouble with the X server crashing when anyone other than root logs in, you may have a full file system (or, a lack of available hard drive space).
To verify that this is the problem you are experiencing, run the following command:
df -h
The df command should help you diagnose which partition is full. For additional information about df and an explanation of the options available (such as the -h option used in this example), refer to the df man page by typing man df at a shell prompt.
A key indicator is 100% full or a percentage above 90% or 95% on a partition. The /home/ and /tmp/ partitions can sometimes fill up quickly with user files. You can make some room on that partition by removing old files. After you free up some disk space, try running X as the user that was unsuccessful before.

6.4.5. Problems When You Try to Log In

If you did not create a user account in the Setup Agent, log in as root and use the password you assigned to root.
If you cannot remember your root password, boot your system as linux single.
Itanium users must enter boot commands with elilo followed by the boot command.
If you are using an x86-based system and GRUB is your installed boot loader, type e for edit when the GRUB boot screen has loaded. You are presented with a list of items in the configuration file for the boot label you have selected.
Choose the line that starts with kernel and type e to edit this boot entry.
At the end of the kernel line, add:
	single
Press Enter to exit edit mode.
Once the boot loader screen has returned, type b to boot the system.
Once you have booted into single user mode and have access to the # prompt, you must type passwd root, which allows you to enter a new password for root. At this point you can type shutdown -r now to reboot the system with the new root password.
If you cannot remember your user account password, you must become root. To become root, type su - and enter your root password when prompted. Then, type passwd <username>. This allows you to enter a new password for the specified user account.
If the graphical login screen does not appear, check your hardware for compatibility issues. The Hardware Compatibility List can be found at:
	http://hardware.redhat.com/hcl/

6.4.6. Is Your RAM Not Being Recognized?

Sometimes, the kernel does not recognize all of your memory (RAM). You can check this with the cat /proc/meminfo command.
Verify that the displayed quantity is the same as the known amount of RAM in your system. If they are not equal, add the following line to the /boot/grub/grub.conf:
mem=xxM
Replace xx with the amount of RAM you have in megabytes.
In /boot/grub/grub.conf, the above example would look similar to the following:
# NOTICE: You have a /boot partition. This means that 
#  all kernel paths are relative to /boot/ 
default=0 
timeout=30 
splashimage=(hd0,0)/grub/splash.xpm.gz 
title Red Hat Enterprise Linux (2.6.9-5.EL)         
root (hd0,0)         
kernel /vmlinuz-2.6.9-5.EL ro root=/dev/hda3 mem=128M
Once you reboot, the changes made to grub.conf are reflected on your system.
Once you have loaded the GRUB boot screen, type e for edit. You are presented with a list of items in the configuration file for the boot label you have selected.
Choose the line that starts with kernel and type e to edit this boot entry.
At the end of the kernel line, add
mem=xxM
where xx equals the amount of RAM in your system.
Press Enter to exit edit mode.
Once the boot loader screen has returned, type b to boot the system.
Itanium users must enter boot commands with elilo followed by the boot command.
Remember to replace xx with the amount of RAM in your system. Press Enter to boot.

6.4.7. Your Printer Does Not Work

If you are not sure how to set up your printer or are having trouble getting it to work properly, try using the Printer Configuration Tool.
Type the system-config-printer command at a shell prompt to launch the Printer Configuration Tool. If you are not root, it prompts you for the root password to continue.

6.4.8. Problems with Sound Configuration

If, for some reason, you do not hear sound and know that you do have a sound card installed, you can run the Sound Card Configuration Tool (system-config-soundcard) utility.
To use the Sound Card Configuration Tool, choose Main Menu => System => Administration => Soundcard Detection in GNOME, or Main Menu => Administration => Soundcard Detection in KDE. A small text box pops up prompting you for your root password.
You can also type the system-config-soundcard command at a shell prompt to launch the Sound Card Configuration Tool. If you are not root, it prompts you for the root password to continue.
If the Sound Card Configuration Tool does not work (if the sample does not play and you still do not have audio sounds), it is likely that your sound card is not yet supported in Red Hat Enterprise Linux.

6.4.9. Apache-based httpd service/Sendmail Hangs During Startup

If you are having trouble with the Apache-based httpd service or Sendmail hanging at startup, make sure the following line is in the /etc/hosts file:
127.0.0.1  localhost.localdomain  localhost

Chapter 7. Updating drivers during installation on Intel and AMD systems

In most cases, Red Hat Enterprise Linux already includes drivers for the devices that make up your system. However, if your system contains hardware that has been released very recently, drivers for this hardware might not yet be included. Sometimes, a driver update that provides support for a new device might be available from Red Hat or your hardware vendor as a ISO image file or a rpm package. Both these formats supply all the files that make up the driver update together in a single file.
Often, you do not need the new hardware during the installation process. For example, if you use a DVD to install to a local hard drive, the installation will succeed even if drivers for your network card are not available. In situations like this, complete the installation and add support for the piece of hardware afterward — refer to Section 23.1, “Driver update rpm packages” for details of using a driver update rpm package to add this support.
In other situations, you might want to add drivers for a device during the installation process to support a particular configuration. For example, you might want to install drivers for a network device or a storage adapter card to give the installer access to the storage devices that your system uses. You can use a driver update image file to add this support during installation in one of three ways:
  1. place the image file in a location accessible to the installer:
    1. on a local IDE hard drive
    2. a USB storage device such as a USB flash drive
    3. on a FTP, HTTP, or NFS server on your local network (or take note of a location on the Internet where someone else has placed the image file)
  2. create a driver update disk by unpacking the image file onto:
    1. a CD (if your computer has an IDE optical drive)
    2. a DVD (if your computer has an IDE optical drive)
    3. a floppy disk
    4. a USB storage device such as a USB flash drive
  3. create an initial ramdisk update from the image file and store it on a PXE server. This is an advanced procedure that you should consider only if you cannot perform a driver update with any other method.
If Red Hat, your hardware vendor, or a trusted third party told you that you will require a driver update during the installation process, choose a method to supply the update from the methods described in this chapter and test it before beginning the installation. Conversely, do not perform a driver update during installation unless you are certain that your system requires it. Although installing an unnecessary driver update will not cause harm, the presence of a driver on a system for which it was not intended can complicate support.

7.1. Limitations of driver updates during installation

Unfortunately, some situations persist in which you cannot use a driver update to provide drivers during installation:
Devices already in use
You cannot use a driver update to replace drivers that the installation program has already loaded. Instead, you must complete the installation with the drivers that the installation program loaded and update to the new drivers after installation, or, if you need the new drivers for the installation process, consider performing an initial RAM disk driver update — refer to Section 7.2.3, “Preparing an initial RAM disk update”.
Devices with an equivalent device available
Because all devices of the same type are initialized together, you cannot update drivers for a device if the installation program has loaded drivers for a similar device. For example, consider a system that has two different network adapters, one of which has a driver update available. The installation program will initialize both adapters at the same time, and therefore, you will not be able to use this driver update. Again, complete the installation with the drivers loaded by the installation program and update to the new drivers after installation, or use an initial RAM disk driver update.

7.2. Preparing for a driver update during installation

If a driver update is necessary and available for your hardware, Red Hat or a trusted third party such as the hardware vendor will provide it in the form of an image file in ISO format. Some methods of performing a driver update require you to make the image file available to the installation program, others require you to use the image file to make a driver update disk, and one requires you to prepare an initial RAM disk update:
Methods that use the image file itself
  • local hard drive (IDE only)
  • USB storage device (for example, USB flash drive)
  • network (HTTP, FTP, NFS)
Methods that use a driver update disk produced from an image file
  • floppy disk
  • CD (IDE only)
  • DVD (IDE only)
  • USB storage device (for example, USB flash drive)
Methods that use an initial RAM disk update
  • PXE
Choose a method to provide the driver update, and refer to Section 7.2.1, “Preparing to use a driver update image file”, Section 7.2.2, “Preparing a driver update disk” or Section 7.2.3, “Preparing an initial RAM disk update”. Note that you can use a USB storage device either to provide an image file, or as a driver update disk.

Important

During installation, you cannot provide driver updates on media that is read by a device with a SATA or SCSI connection. For example, if the only optical drive on your system is a DVD drive with a SATA connection, you cannot provide a driver update on CD or DVD.

7.2.1. Preparing to use a driver update image file

7.2.1.1. Preparing to use an image file on local storage

To make the ISO image file available on local storage, such as a USB flash drive, USB hard drive, or local IDE hard drive, simply copy the file onto the storage device. You can rename the file if you find it helpful to do so, but you must not change the filename extension, which must remain .iso. In the following example, the file is named dd.iso:
Content of a USB flash drive holding a driver update image file

Figure 7.1. Content of a USB flash drive holding a driver update image file

Note that if you use this method, the storage device will contain only a single file. This differs from driver update disks on formats such as CD and DVD, which contain many files. The ISO image file contains all of the files that would normally be on a driver update disk.
If you change the file system label of the device to OEMDRV, the installation program will automatically examine it for driver updates and load any that it detects. This behavior is controlled by the dlabel=on boot option, which is enabled by default. Refer to Section 7.3.1, “Let the installer automatically find a driver update disk”.

7.2.1.2. Preparing to use an image file available through a network

To make the ISO image file available on a local network, place it in a publicly accessible folder on a HTTP, FTP, or NFS server. If you plan to use an image file that is already publicly available through the Internet, no special preparation is necessary. In either case, take note of the URL and verify that you can access the file from another machine on your network before commencing installation.

7.2.2. Preparing a driver update disk

You can use a variety of media to create a driver update disk, including CD, DVD, floppy disk, and USB storage devices such as USB flash drives

7.2.2.1. Creating a driver update disk on CD or DVD

Important

CD/DVD Creator is part of the GNOME desktop. If you use a different Linux desktop, or a different operating system altogether, you will need to use another piece of software to create the CD or DVD. The steps will be generally similar.
Make sure that the software that you choose can create CDs or DVDs from image files. While this is true of most CD and DVD burning software, exceptions exist. Look for a button or menu entry labeled burn from image or similar. If your software lacks this feature, or you do not select it, the resulting disk will hold only the image file itself, instead of the contents of the image file.
  1. Use the desktop file manager to locate the driver update ISO image file supplied to you by Red Hat or your hardware vendor.
    A typical .iso file displayed in a file manager window

    Figure 7.2. A typical .iso file displayed in a file manager window

  2. Right-click on this file and choose Write to disc. You will see a window similar to the following:
    CD/DVD Creator's Write to Disc dialog

    Figure 7.3. CD/DVD Creator's Write to Disc dialog

  3. Click the Write button. If a blank disc is not already in the drive, CD/DVD Creator will prompt you to insert one.
After you burn a driver update disk CD or DVD, verify that the disk was created successfully by inserting it into your system and browsing to it using the file manager. You should see a list of files similar to the following:
Contents of a typical driver update disc on CD or DVD

Figure 7.4. Contents of a typical driver update disc on CD or DVD

If you see only a single file ending in .iso, then you have not created the disk correctly and should try again. Ensure that you choose an option similar to burn from image if you use a Linux desktop other than GNOME or if you use a different operating system.

7.2.2.2. Creating a driver update disk on floppy disk, or USB storage device

Important

The following procedure assumes that you are creating a driver update disk using Linux. To create a driver update disk using a different operating system, you will need to find a tool that can extract files from ISO images. You must then place the extracted files on a removable disk or USB storage device.

Warning

If you perform this procedure with a disk or USB storage device that already contains data, this data will be destroyed with no warning. Make sure that you specify the correct disk or USB storage device, and make sure that this disk or storage device does not contain any data that you want to keep.
  1. Insert a blank, formatted floppy disk into an available drive, or connect an empty USB storage device (such as a USB flash drive) to your computer. Note the device name allocated to this disk, for example, /dev/fd0 for a floppy disk in the first floppy drive on your system.
    If you do not know the device name, become root and use the command fdisk -l on the command line. You will see a list of all storage devices available on your system. Compare the output of fdisk -l when the disk inserted or the storage device is attached with the output of this command when the disk is removed or the storage device is disconnected.
  2. At the command line, change into the directory that contains the image file.
  3. At the command line, type:
    dd if=image of=device
    where image is the image file, and device is the device name. For example, to create a driver disk on floppy disk /dev/fd0 from driver update image file dd.iso, you would use:
    dd if=dd.iso of=/dev/fd0
After you create a driver update disk, insert it (if you used a disk) or attach it (if you used a USB storage device) and browse to it using the file manager. If you see a list of files similar to those illustrated in Figure 7.4, “Contents of a typical driver update disc on CD or DVD”, you know that you have created the driver update disk correctly.

7.2.3. Preparing an initial RAM disk update

Important

This is an advanced procedure that you should consider only if you cannot perform a driver update with any other method.
The Red Hat Enterprise Linux installation program can load updates for itself early in the installation process from a RAM disk — an area of your computer's memory that temporarily behaves as if it were a disk. You can use this same capability to load driver updates. To perform a driver update during installation, your computer must be able to boot from a preboot execution environment (PXE) server, and you must have a PXE server available on your network. Refer to Chapter 34, PXE Network Installations for instructions on using PXE during installation.
To make the driver update available on your PXE server:
  1. Place the driver update image file on your PXE server. Usually, you would do this by downloading it to the PXE server from a location on the Internet specified by Red Hat or your hardware vendor. Names of driver update image files end in .iso.
  2. Copy the driver update image file into the /tmp/initrd_update directory.
  3. Rename the driver update image file to dd.img.
  4. At the command line, change into the /tmp/initrd_update directory, type the following command, and press Enter:
    find . | cpio --quiet -c -o | gzip -9 >/tmp/initrd_update.img
    
  5. Copy the file /tmp/initrd_update.img into the directory the holds the target that you want to use for installation. This directory is placed under the /tftpboot/pxelinux/ directory. For example, /tftpboot/pxelinux/r5su3/ might hold the PXE target for Red Hat Enterprise Linux 5.3 Server.
  6. Edit the /tftpboot/pxelinux/pxelinux.cfg/default file to include an entry that includes the initial RAM disk update that you just created, in the following format:
    label target-dd
    kernel target/vmlinuz
    append initrd=target/initrd.img,target/dd.img
    
    Where target is the target that you want to use for installation.

Example 7.1. Preparing an initial RAM disk update from a driver update image file

In this example, driver_update.iso is a driver update image file that you downloaded from the Internet to a directory on your PXE server. The target that you want to PXE boot from is located in /tftpboot/pxelinux/r5su3
At the command line, change to the directory that holds the file and enter the following commands:
$ cp driver_update.iso /tmp/initrd_update/dd.img
$ cd /tmp/initrd_update
$ find . | cpio --quiet -c -o | gzip -9 >/tmp/initrd_update.img
$ cp /tmp/initrd_update.img /tftpboot/pxelinux/r5su3/dd.img
Edit the /tftpboot/pxelinux/pxelinux.cfg/default file and include the following entry:
label r5su3-dd
kernel r5su3/vmlinuz
append initrd=r5su3/initrd.img,r5su3/dd.img
Refer to Section 7.3.5, “Select a PXE target that includes a driver update” to learn how to use an initial RAM disk update during installation.

7.3. Performing a driver update during installation

You can perform a driver update during installation in the following ways:
  • let the installer automatically find a driver update disk.
  • let the installer prompt you for a driver update.
  • use a boot option to specify a driver update disk.
  • use a boot option to specify a driver update image file on a network.
  • select a PXE target that includes a driver update.

7.3.1. Let the installer automatically find a driver update disk

Attach a block device with the filesystem label OEMDRV before starting the installation process. The installer will automatically examine the device and load any driver updates that it detects and will not prompt you during the process. Refer to Section 7.2.1.1, “Preparing to use an image file on local storage” to prepare a storage device for the installer to find.

7.3.2. Let the installer prompt you for a driver update

  1. Begin the installation normally for whatever method you have chosen. If the installer cannot load drivers for a piece of hardware that is essential for the installation process (for example, if it cannot detect any network or storage controllers), it prompts you to insert a driver update disk:
    The no driver found dialog

    Figure 7.5. The no driver found dialog

7.3.3. Use a boot option to specify a driver update disk

Important

This method only works to introduce completely new drivers, not to update existing drivers.
  1. Type linux dd at the boot prompt at the start of the installation process and press Enter. The installer prompts you to confirm that you have a driver disk:
    The driver disk prompt

    Figure 7.6. The driver disk prompt

  2. Insert the driver update disk that you created on CD, DVD, floppy disk, or USB storage device and select Yes. The installer examines the storage devices that it can detect. If there is only one possible location that could hold a driver disk (for example, the installer detects the presence of a floppy disk, but no other storage devices) it will automatically load any driver updates that it finds at this location.
    If the installer finds more than one location that could hold a driver update, it prompts you to specify the location of the update. Refer to to Section 7.4, “Specifying the location of a driver update image file or driver update disk” .

7.3.4. Use a boot option to specify a driver update image file on a network

Important

This method only works to introduce completely new drivers, not to update existing drivers.
Type linux dd=URL (where URL is the HTTP, FTP, or NFS address of a driver update image) at the boot prompt at the start of the installation process and press Enter. The installer will retrieve the driver update image from that address and use it during installation.

7.3.5. Select a PXE target that includes a driver update

  1. Select network boot in your computer's BIOS or boot menu. The procedure to specify this option varies widely among different computers. Consult your hardware documentation or the hardware vendor for specifics relevant to your computer.
  2. In the preexecution boot environment (PXE), choose the boot target that you prepared on your PXE server. For example, if you labeled this environment r5su3-dd in the /tftpboot/pxelinux/pxelinux.cfg/default file on your PXE server, type r5su3-dd at the prompt and press Enter.
Refer to Section 7.2.3, “Preparing an initial RAM disk update” and Chapter 34, PXE Network Installations for instructions on using PXE to perform an update during installation. Note that this is an advanced procedure — do not attempt it unless other methods of performing a driver update fail.

7.4. Specifying the location of a driver update image file or driver update disk

If the installer detects more than one possible device that could hold a driver update, it prompts you to select the correct device. If you are not sure which option represents the device on which the driver update is stored, try the various options in order until you find the correct one.
Selecting a driver disk source

Figure 7.7. Selecting a driver disk source

If the device that you choose contains no suitable update media, the installer will prompt you to make another choice.
If you made a driver update disk on floppy disk, CD, DVD, or USB storage device, the installer now loads the driver update. However, if the device that you selected is a type of device that could contain more than one partition (whether the device currently has more than one partition or not), the installer might prompt you to select the partition that holds the driver update.
Selecting a driver disk partition

Figure 7.8. Selecting a driver disk partition

The installer prompts you to specify which file contains the driver update:
Selecting an ISO image

Figure 7.9. Selecting an ISO image

Expect to see these screens if you stored the driver update on an internal hard drive or on a USB storage device. You should not see them if the driver update is on a floppy disk, CD, or DVD.
Regardless of whether you are providing a driver update in the form of an image file or with a driver update disk, the installer now copies the appropriate update files into a temporary storage area (located in system RAM and not on disk). The installer might ask whether you would like to use additional driver updates. If you select Yes, you can load additional updates in turn. When you have no further driver updates to load, select No. If you stored the driver update on removeable media, you can now safely eject or disconnect the disk or device. The installer no longer requires the driver update, and you can re-use the media for other purposes.

Chapter 8. Additional Boot Options for Intel® and AMD Systems

This section discusses additional boot and kernel boot options available for the Red Hat Enterprise Linux installation program.
To use any of the boot options presented here, type the command you wish to invoke at the installation boot: prompt.

Boot Time Command Arguments

askmethod
this command asks you to select the installation method you would like to use when booting from the Red Hat Enterprise Linux CD-ROM.
apic
this x86 boot command works around a bug commonly encountered in the Intel 440GX chipset BIOS and should only be executed with the installation program kernel.
dd
this argument causes the installation program to prompt you to use a driver diskette.
dd=url
this argument causes the installation program to prompt you to use a driver image from a specified HTTP, FTP, or NFS network address.
display=ip:0
this command allows remote display forwarding. In this command, ip should be replaced with the IP address of the system on which you want the display to appear.
On the system you want the display to appear on, you must execute the command xhost +remotehostname, where remotehostname is the name of the host from which you are running the original display. Using the command xhost +remotehostname limits access to the remote display terminal and does not allow access from anyone or any system not specifically authorized for remote access.
driverdisk
this command performs the same function as the dd command and also prompts you to use a driver diskette during the installation of Red Hat Enterprise Linux.
linux upgradeany
this command relaxes some of the checks on your /etc/redhat-release file. If your /etc/redhat-release file has been changed from the default, your Red Hat Enterprise Linux installation may not be found when attempting an upgrade to Red Hat Enterprise Linux 5. Use this option only if your existing Red Hat Enterprise Linux installation was not detected.
mediacheck
this command gives you the option of testing the integrity of the install source (if an ISO-based method). this command works with the CD, DVD, hard drive ISO, and NFS ISO installation methods. Verifying that the ISO images are intact before you attempt an installation helps to avoid problems that are often encountered during an installation.
mem=xxxm
this command allows you to override the amount of memory the kernel detects for the machine. This may be needed for some older systems where only 16 mb is detected and for some new machines where the video card shares the video memory with the main memory. When executing this command, xxx should be replaced with the amount of memory in megabytes.
mpath
enables multipath support.

Important

If you install Red Hat Enterprise Linux 5.11 on a network storage device accessible through multiple paths, you must boot the installation process with this option. If you do not specify this option at boot time, installation will fail, or the system will fail to boot after installation completes.
nmi_watchdog=1
this command enables the built-in kernel deadlock detector. This command can be used to debug hard kernel lockups. by executing periodic NMI (Non Maskable Interrupt) interrupts, the kernel can monitor whether any CPU has locked up and print out debugging messages as needed.
noapic
this x86 boot command tells the kernel not to use the APIC chip. It may be helpful for some motherboards with a bad APIC (such as the Abit BP6) or with a buggy bios. systems based on the nvidia nforce3 chipset (such as the Asus SK8N) have been known to hang during IDE detection at boot time, or display other interrupt-delivery issues.
noeject
do not eject optical discs after installation. This option is useful in remote installations where it is difficult to close the tray afterwards.
nomce
this x86 boot command disables self-diagnosis checks performed on the CPU. the kernel enables self-diagnosis on the CPU by default (called machine check exception). Early Compaq Pentium systems may need this option as they do not support processor error checking correctly. A few other laptops, notably those using the Radeon IGP chipset, may also need this option.
nonet
this command disables network hardware probing.
nopass
this command disables the passing of keyboard and mouse information to stage 2 of the installation program. It can be used to test keyboard and mouse configuration screens during stage 2 of the installation program when performing a network installation.
nopcmcia
this command ignores any PCMCIA controllers in system.
noprobe
this command disables hardware detection and instead prompts the user for hardware information.
noshell
this command disables shell access on virtual console 2 during an installation.
nostorage
this command disables probing for SCSI and RAID storage hardware.
nousb
this command disables the loading of USB support during the installation. If the installation program tends to hang early in the process, this command may be helpful.
nousbstorage
this command disables the loading of the usbstorage module in the installation program's loader. It may help with device ordering on SCSI systems.
numa=off
Red Hat Enterprise Linux supports NUMA (non-uniform memory access) on the AMD64 architecture. while all cpus can access all memory even without numa support, the numa support present in the updated kernel causes memory allocations to favor the cpu on which they originate as much as possible, thereby minimizing inter-CPU memory traffic. This can provide significant performance improvements in certain applications. to revert to the original non-NUMA behavior, specify this boot option.
reboot=b
this x86, AMD64, and Intel® EM64T boot command changes the way the kernel tries to reboot the machine. If a kernel hang is experienced while the system is shutting down, this command may cause the system to reboot successfully.
rescue
this command runs rescue mode. Refer to Chapter 27, Basic System Recovery for more information about rescue mode.
resolution=
tells the installation program which video mode to run. it accepts any standard resolution, such as 640x480, 800x600, 1024x768, and so on.
serial
this command turns on serial console support.
text
this command disables the graphical installation program and forces the installation program to run in text mode.
updates
this command prompts you to insert a floppy diskette containing updates (bug fixes) for the anaconda installation program. It is not needed if you are performing a network installation and have already placed the updates image contents in rhupdates/ on the server.
updates=
this command allows you to specify a URL to retrieve updates (bug fixes) for the anaconda installation program.
vnc
this command allows you to install from a VNC server.
vncpassword=
this command sets the password used to connect to the VNC server.

Important

Other kernel boot options have no particular meaning for anaconda and do not affect the installation process. However, if you use these options to boot the installation system, anaconda will preserve them in the bootloader configuration.

Chapter 9. The GRUB Boot Loader

When a computer with Red Hat Enterprise Linux is turned on, the operating system is loaded into memory by a special program called a boot loader. A boot loader usually exists on the system's primary hard drive (or other media device) and has the sole responsibility of loading the Linux kernel with its required files or (in some cases) other operating systems into memory.

9.1. Boot Loaders and System Architecture

Each architecture capable of running Red Hat Enterprise Linux uses a different boot loader. The following table lists the boot loaders available for each architecture:

Table 9.1. Boot Loaders by Architecture

Architecture Boot Loaders
AMD® AMD64 GRUB
IBM® eServerSystem i OS/400®
IBM® eServerSystem p YABOOT
IBM® System z® z/IPL
IBM® System z® z/IPL
Intel® Itanium ELILO
x86 GRUB
This chapter discusses commands and configuration options for the GRUB boot loader included with Red Hat Enterprise Linux for the x86 architecture.

9.2. GRUB

The GNU GRand Unified Boot loader (GRUB) is a program which enables the selection of the installed operating system or kernel to be loaded at system boot time. It also allows the user to pass arguments to the kernel.

9.2.1. GRUB and the x86 Boot Process

This section discusses the specific role GRUB plays when booting an x86 system. For a look at the overall boot process, refer to Section 33.2, “A Detailed Look at the Boot Process”.
GRUB loads itself into memory in the following stages:
  1. The Stage 1 or primary boot loader is read into memory by the BIOS from the MBR[4]. The primary boot loader exists on less than 512 bytes of disk space within the MBR and is capable of loading either the Stage 1.5 or Stage 2 boot loader.
  2. The Stage 1.5 boot loader is read into memory by the Stage 1 boot loader, if necessary. Some hardware requires an intermediate step to get to the Stage 2 boot loader. This is sometimes true when the /boot/ partition is above the 1024 cylinder head of the hard drive or when using LBA mode. The Stage 1.5 boot loader is found either on the /boot/ partition or on a small part of the MBR and the /boot/ partition.
  3. The Stage 2 or secondary boot loader is read into memory. The secondary boot loader displays the GRUB menu and command environment. This interface allows the user to select which kernel or operating system to boot, pass arguments to the kernel, or look at system parameters.
  4. The secondary boot loader reads the operating system or kernel as well as the contents of /boot/sysroot/ into memory. Once GRUB determines which operating system or kernel to start, it loads it into memory and transfers control of the machine to that operating system.
The method used to boot Red Hat Enterprise Linux is called direct loading because the boot loader loads the operating system directly. There is no intermediary between the boot loader and the kernel.
The boot process used by other operating systems may differ. For example, the Microsoft® Windows® operating system, as well as other operating systems, are loaded using chain loading. Under this method, the MBR points to the first sector of the partition holding the operating system, where it finds the files necessary to actually boot that operating system.
GRUB supports both direct and chain loading boot methods, allowing it to boot almost any operating system.

Warning

During installation, Microsoft's DOS and Windows installation programs completely overwrite the MBR, destroying any existing boot loaders. If creating a dual-boot system, it is best to install the Microsoft operating system first.

9.2.2. Features of GRUB

GRUB contains several features that make it preferable to other boot loaders available for the x86 architecture. Below is a partial list of some of the more important features:
  • GRUB provides a true command-based, pre-OS environment on x86 machines. This feature affords the user maximum flexibility in loading operating systems with specified options or gathering information about the system. For years, many non-x86 architectures have employed pre-OS environments that allow system booting from a command line.
  • GRUB supports Logical Block Addressing (LBA) mode. LBA places the addressing conversion used to find files in the hard drive's firmware, and is used on many IDE and all SCSI hard devices. Before LBA, boot loaders could encounter the 1024-cylinder BIOS limitation, where the BIOS could not find a file after the 1024 cylinder head of the disk. LBA support allows GRUB to boot operating systems from partitions beyond the 1024-cylinder limit, so long as the system BIOS supports LBA mode. Most modern BIOS revisions support LBA mode.
  • GRUB can read ext2 partitions. This functionality allows GRUB to access its configuration file, /boot/grub/grub.conf, every time the system boots, eliminating the need for the user to write a new version of the first stage boot loader to the MBR when configuration changes are made. The only time a user needs to reinstall GRUB on the MBR is if the physical location of the /boot/ partition is moved on the disk. For details on installing GRUB to the MBR, refer to Section 9.3, “Installing GRUB”.

9.3. Installing GRUB

If GRUB was not installed during the installation process, it can be installed afterward. Once installed, it automatically becomes the default boot loader.
Before installing GRUB, make sure to use the latest GRUB package available or use the GRUB package from the installation CD-ROMs. For instructions on installing packages, see the chapter titled Package Management with RPM in the Red Hat Enterprise Linux Deployment Guide.
Once the GRUB package is installed, open a root shell prompt and run the command /sbin/grub-install <location>, where <location> is the location that the GRUB Stage 1 boot loader should be installed. For example, the following command installs GRUB to the MBR of the master IDE device on the primary IDE bus:
/sbin/grub-install /dev/hda
The next time the system boots, the GRUB graphical boot loader menu appears before the kernel loads into memory.

Important

GRUB cannot construct a software RAID. Therefore, the /boot directory must reside on a single, specific disk partition. The /boot directory cannot be striped across multiple disks, as in a level 0 RAID. To use a level 0 RAID on your system, place /boot on a separate partition outside the RAID.
Similarly, because the /boot directory must reside on a single, specific disk partition, GRUB cannot boot the system if the disk holding that partition fails or is removed from the system. This is true even if the disk is mirrored in a level 1 RAID. The following Red Hat Knowledgebase article describes how to make the system bootable from another disk in the mirrored set: http://kbase.redhat.com/faq/docs/DOC-7095
Note that these issues apply only to RAID that is implemented in software, where the individual disks that make up the array are still visible as individual disks on the system. These issues do not apply to hardware RAID where multiple disks are represented as a single device.

9.4. GRUB Terminology

One of the most important things to understand before using GRUB is how the program refers to devices, such as hard drives and partitions. This information is particularly important when configuring GRUB to boot multiple operating systems.

9.4.1. Device Names

When referring to a specific device with GRUB, do so using the following format (note that the parentheses and comma are very important syntactically):
(<type-of-device><bios-device-number>,<partition-number>)
The <type-of-device> specifies the type of device from which GRUB boots. The two most common options are hd for a hard disk or fd for a 3.5 diskette. A lesser used device type is also available called nd for a network disk. Instructions on configuring GRUB to boot over the network are available online at http://www.gnu.org/software/grub/manual/.
The <bios-device-number> is the BIOS device number. The primary IDE hard drive is numbered 0 and a secondary IDE hard drive is numbered 1. This syntax is roughly equivalent to that used for devices by the kernel. For example, the a in hda for the kernel is analogous to the 0 in hd0 for GRUB, the b in hdb is analogous to the 1 in hd1, and so on.
The <partition-number> specifies the number of a partition on a device. Like the <bios-device-number>, most types of partitions are numbered starting at 0. However, BSD partitions are specified using letters, with a corresponding to 0, b corresponding to 1, and so on.

Note

The numbering system for devices under GRUB always begins with 0, not 1. Failing to make this distinction is one of the most common mistakes made by new users.
To give an example, if a system has more than one hard drive, GRUB refers to the first hard drive as (hd0) and the second as (hd1). Likewise, GRUB refers to the first partition on the first drive as (hd0,0) and the third partition on the second hard drive as (hd1,2).
In general the following rules apply when naming devices and partitions under GRUB:
  • It does not matter if system hard drives are IDE or SCSI, all hard drives begin with the letters hd. The letters fd are used to specify 3.5 diskettes.
  • To specify an entire device without respect to partitions, leave off the comma and the partition number. This is important when telling GRUB to configure the MBR for a particular disk. For example, (hd0) specifies the MBR on the first device and (hd3) specifies the MBR on the fourth device.
  • If a system has multiple drive devices, it is very important to know how the drive boot order is set in the BIOS. This is a simple task if a system has only IDE or SCSI drives, but if there is a mix of devices, it becomes critical that the type of drive with the boot partition be accessed first.

9.4.2. File Names and Blocklists

When typing commands to GRUB that reference a file, such as a menu list, it is necessary to specify an absolute file path immediately after the device and partition numbers.
The following illustrates the structure of such a command:
(<device-type><device-number>,<partition-number>)</path/to/file>
In this example, replace <device-type> with hd, fd, or nd. Replace <device-number> with the integer for the device. Replace </path/to/file> with an absolute path relative to the top-level of the device.
It is also possible to specify files to GRUB that do not actually appear in the file system, such as a chain loader that appears in the first few blocks of a partition. To load such files, provide a blocklist that specifies block by block where the file is located in the partition. Since a file is often comprised of several different sets of blocks, blocklists use a special syntax. Each block containing the file is specified by an offset number of blocks, followed by the number of blocks from that offset point. Block offsets are listed sequentially in a comma-delimited list.
The following is a sample blocklist:
0+50,100+25,200+1
This sample blocklist specifies a file that starts at the first block on the partition and uses blocks 0 through 49, 100 through 124, and 200.
Knowing how to write blocklists is useful when using GRUB to load operating systems which require chain loading. It is possible to leave off the offset number of blocks if starting at block 0. As an example, the chain loading file in the first partition of the first hard drive would have the following name:
(hd0,0)+1
The following shows the chainloader command with a similar blocklist designation at the GRUB command line after setting the correct device and partition as root:
chainloader +1

9.4.3. The Root File System and GRUB

The use of the term root file system has a different meaning in regard to GRUB. It is important to remember that GRUB's root file system has nothing to do with the Linux root file system.
The GRUB root file system is the top level of the specified device. For example, the image file (hd0,0)/grub/splash.xpm.gz is located within the /grub/ directory at the top-level (or root) of the (hd0,0) partition (which is actually the /boot/ partition for the system).
Next, the kernel command is executed with the location of the kernel file as an option. Once the Linux kernel boots, it sets up the root file system that Linux users are familiar with. The original GRUB root file system and its mounts are forgotten; they only existed to boot the kernel file.
Refer to the root and kernel commands in Section 9.6, “GRUB Commands” for more information.

9.5. GRUB Interfaces

GRUB features three interfaces which provide different levels of functionality. Each of these interfaces allows users to boot the Linux kernel or another operating system.
The interfaces are as follows:

Note

The following GRUB interfaces can only be accessed by pressing any key within the three seconds of the GRUB menu bypass screen.
Menu Interface
This is the default interface shown when GRUB is configured by the installation program. A menu of operating systems or preconfigured kernels are displayed as a list, ordered by name. Use the arrow keys to select an operating system or kernel version and press the Enter key to boot it. If you do nothing on this screen, then after the time out period expires GRUB will load the default option.
Press the e key to enter the entry editor interface or the c key to load a command line interface.
Refer to Section 9.7, “GRUB Menu Configuration File” for more information on configuring this interface.
Menu Entry Editor Interface
To access the menu entry editor, press the e key from the boot loader menu. The GRUB commands for that entry are displayed here, and users may alter these command lines before booting the operating system by adding a command line (o inserts a new line after the current line and O inserts a new line before it), editing one (e), or deleting one (d).
After all changes are made, the b key executes the commands and boots the operating system. The Esc key discards any changes and reloads the standard menu interface. The c key loads the command line interface.

Note

For information about changing runlevels using the GRUB menu entry editor, refer to Section 9.8, “Changing Runlevels at Boot Time”.
Command Line Interface
The command line interface is the most basic GRUB interface, but it is also the one that grants the most control. The command line makes it possible to type any relevant GRUB commands followed by the Enter key to execute them. This interface features some advanced shell-like features, including Tab key completion based on context, and Ctrl key combinations when typing commands, such as Ctrl+a to move to the beginning of a line and Ctrl+e to move to the end of a line. In addition, the arrow, Home, End, and Delete keys work as they do in the bash shell.
Refer to Section 9.6, “GRUB Commands” for a list of common commands.

9.5.1. Interfaces Load Order

When GRUB loads its second stage boot loader, it first searches for its configuration file. Once found, the menu interface bypass screen is displayed. If a key is pressed within three seconds, GRUB builds a menu list and displays the menu interface. If no key is pressed, the default kernel entry in the GRUB menu is used.
If the configuration file cannot be found, or if the configuration file is unreadable, GRUB loads the command line interface, allowing the user to type commands to complete the boot process.
If the configuration file is not valid, GRUB prints out the error and asks for input. This helps the user see precisely where the problem occurred. Pressing any key reloads the menu interface, where it is then possible to edit the menu option and correct the problem based on the error reported by GRUB. If the correction fails, GRUB reports an error and reloads the menu interface.

9.6. GRUB Commands

GRUB allows a number of useful commands in its command line interface. Some of the commands accept options after their name; these options should be separated from the command and other options on that line by space characters.
The following is a list of useful commands:
  • boot — Boots the operating system or chain loader that was last loaded.
  • chainloader </path/to/file> — Loads the specified file as a chain loader. If the file is located on the first sector of the specified partition, use the blocklist notation, +1, instead of the file name.
    The following is an example chainloader command:
    chainloader +1
  • displaymem — Displays the current use of memory, based on information from the BIOS. This is useful to determine how much RAM a system has prior to booting it.
  • initrd </path/to/initrd> — Enables users to specify an initial RAM disk to use when booting. An initrd is necessary when the kernel needs certain modules in order to boot properly, such as when the root partition is formatted with the ext3 file system.
    The following is an example initrd command:
    initrd /initrd-2.6.8-1.523.img
  • install <stage-1> <install-disk> <stage-2> p config-file — Installs GRUB to the system MBR.
    • <stage-1> — Signifies a device, partition, and file where the first boot loader image can be found, such as (hd0,0)/grub/stage1.
    • <install-disk> — Specifies the disk where the stage 1 boot loader should be installed, such as (hd0).
    • <stage-2> — Passes the stage 2 boot loader location to the stage 1 boot loader, such as (hd0,0)/grub/stage2.
    • p <config-file> — This option tells the install command to look for the menu configuration file specified by <config-file>, such as (hd0,0)/grub/grub.conf.

    Warning

    The install command overwrites any information already located on the MBR.
  • kernel </path/to/kernel> <option-1> <option-N> ... — Specifies the kernel file to load when booting the operating system. Replace </path/to/kernel> with an absolute path from the partition specified by the root command. Replace <option-1> with options for the Linux kernel, such as root=/dev/VolGroup00/LogVol00 to specify the device on which the root partition for the system is located. Multiple options can be passed to the kernel in a space separated list.
    The following is an example kernel command:
    kernel /vmlinuz-2.6.8-1.523 ro root=/dev/VolGroup00/LogVol00
    The option in the previous example specifies that the root file system for Linux is located on the hda5 partition.
  • root (<device-type><device-number>,<partition>) — Configures the root partition for GRUB, such as (hd0,0), and mounts the partition.
    The following is an example root command:
    root (hd0,0)
  • rootnoverify (<device-type><device-number>,<partition>) — Configures the root partition for GRUB, just like the root command, but does not mount the partition.
Other commands are also available; type help --all for a full list of commands. For a description of all GRUB commands, refer to the documentation available online at http://www.gnu.org/software/grub/manual/.

9.7. GRUB Menu Configuration File

The configuration file (/boot/grub/grub.conf), which is used to create the list of operating systems to boot in GRUB's menu interface, essentially allows the user to select a pre-set group of commands to execute. The commands given in Section 9.6, “GRUB Commands” can be used, as well as some special commands that are only available in the configuration file.

9.7.1. Configuration File Structure

The GRUB menu interface configuration file is /boot/grub/grub.conf. The commands to set the global preferences for the menu interface are placed at the top of the file, followed by stanzas for each operating kernel or operating system listed in the menu.
The following is a very basic GRUB menu configuration file designed to boot either Red Hat Enterprise Linux or Microsoft Windows 2000:
default=0 
timeout=10 
splashimage=(hd0,0)/grub/splash.xpm.gz 
hiddenmenu 
title Red Hat Enterprise Linux Server (2.6.18-2.el5PAE)         
root (hd0,0)         
kernel /boot/vmlinuz-2.6.18-2.el5PAE ro root=LABEL=/1 rhgb quiet       
initrd /boot/initrd-2.6.18-2.el5PAE.img

# section to load Windows 
title Windows         
rootnoverify (hd0,0)         
chainloader +1
This file configures GRUB to build a menu with Red Hat Enterprise Linux as the default operating system and sets it to autoboot after 10 seconds. Two sections are given, one for each operating system entry, with commands specific to the system disk partition table.

Note

Note that the default is specified as an integer. This refers to the first title line in the GRUB configuration file. For the Windows section to be set as the default in the previous example, change the default=0 to default=1.
Configuring a GRUB menu configuration file to boot multiple operating systems is beyond the scope of this chapter. Consult Section 9.9, “Additional Resources” for a list of additional resources.

9.7.2. Configuration File Directives

The following are directives commonly used in the GRUB menu configuration file:
  • chainloader </path/to/file> — Loads the specified file as a chain loader. Replace </path/to/file> with the absolute path to the chain loader. If the file is located on the first sector of the specified partition, use the blocklist notation, +1.
  • color <normal-color> <selected-color> — Allows specific colors to be used in the menu, where two colors are configured as the foreground and background. Use simple color names such as red/black. For example:
    color red/black green/blue
  • default=<integer> — Replace <integer> with the default entry title number to be loaded if the menu interface times out.
  • fallback=<integer> — Replace <integer> with the entry title number to try if the first attempt fails.
  • hiddenmenu — Prevents the GRUB menu interface from being displayed, loading the default entry when the timeout period expires. The user can see the standard GRUB menu by pressing the Esc key.
  • initrd </path/to/initrd> — Enables users to specify an initial RAM disk to use when booting. Replace </path/to/initrd> with the absolute path to the initial RAM disk.
  • kernel </path/to/kernel> <option-1> <option-N> — Specifies the kernel file to load when booting the operating system. Replace </path/to/kernel> with an absolute path from the partition specified by the root directive. Multiple options can be passed to the kernel when it is loaded.
  • password=<password> — Prevents a user who does not know the password from editing the entries for this menu option.
    Optionally, it is possible to specify an alternate menu configuration file after the password=<password> directive. In this case, GRUB restarts the second stage boot loader and uses the specified alternate configuration file to build the menu. If an alternate menu configuration file is left out of the command, a user who knows the password is allowed to edit the current configuration file.
    For more information about securing GRUB, see the chapter titled Workstation Security in the Red Hat Enterprise Linux Deployment Guide.
  • root (<device-type><device-number>,<partition>) — Configures the root partition for GRUB, such as (hd0,0), and mounts the partition.
  • rootnoverify (<device-type><device-number>,<partition>) — Configures the root partition for GRUB, just like the root command, but does not mount the partition.
  • timeout=<integer> — Specifies the interval, in seconds, that GRUB waits before loading the entry designated in the default command.
  • splashimage=<path-to-image> — Specifies the location of the splash screen image to be used when GRUB boots.
  • title group-title — Specifies a title to be used with a particular group of commands used to load a kernel or operating system.
To add human-readable comments to the menu configuration file, begin the line with the hash mark character (#).

9.8. Changing Runlevels at Boot Time

Under Red Hat Enterprise Linux, it is possible to change the default runlevel at boot time.
To change the runlevel of a single boot session, use the following instructions:
  • When the GRUB menu bypass screen appears at boot time, press any key to enter the GRUB menu (within the first three seconds).
  • Press the a key to append to the kernel command.
  • Add <space><runlevel> at the end of the boot options line to boot to the desired runlevel. For example, the following entry would initiate a boot process into runlevel 3:
    grub append> ro root=/dev/VolGroup00/LogVol00 rhgb quiet 3

9.9. Additional Resources

This chapter is only intended as an introduction to GRUB. Consult the following resources to discover more about how GRUB works.

9.9.1. Installed Documentation

  • /usr/share/doc/grub-<version-number>/ — This directory contains good information about using and configuring GRUB, where <version-number> corresponds to the version of the GRUB package installed.
  • info grub — The GRUB info page contains a tutorial, a user reference manual, a programmer reference manual, and a FAQ document about GRUB and its usage.

9.9.2. Useful Websites



[4] For more on the system BIOS and the MBR, refer to Section 33.2.1, “The BIOS”.

Chapter 10. Additional Resources about Itanium and Linux

Other reference materials, related to running Red Hat Enterprise Linux on an Itanium system, are available on the Web. A few of the available resources are as follows:

Part II. IBM POWER Architecture - Installation and Booting

The Red Hat Enterprise Linux Installation Guide for IBM POWER systems discusses the installation of Red Hat Enterprise Linux and some basic post-installation troubleshooting. Advanced installation options are covered in the second part of this manual.

Chapter 11. Steps to Get You Started

11.1. Upgrade or Install?

For information to help you determine whether to perform an upgrade or an installation refer to Chapter 24, Upgrading Your Current System.

11.2. Preparation for IBM eServer System p and System i

The IBM eServer System p and IBM eServer System i systems introduce many options for partitioning, virtual or native devices, and consoles. Both versions of the system use the same kernel and have many of the same options available, depending on the system configuration.
If you are using a non-partitioned System p system, you do not need any pre-installation setup. For systems using the HVSI serial console, hook up your console to the T2 serial port.
If using a partitioned system, whether IBM System p or IBM System i the steps to create the partition and start the installation are largely the same. You should create the partition at the HMC and assign some CPU and memory resources, as well as SCSI and Ethernet resources, which can be either virtual or native. The HMC create partition wizard steps you through the creation.
For more information on creating the partition, refer to IBM's Infocenter article on Configuring Linux logical partitions available online at: http://publib.boulder.ibm.com/infocenter/eserver/v1r3s/index.jsp?topic=/iphbi/iphbikickoff.htm
If you are using virtual SCSI resources, rather than native SCSI, you must configure a 'link' to the virtual SCSI serving partition, and then configure the virtual SCSI serving partition itself. You create a 'link' between the virtual SCSI client and server slots using the HMC. You can configure a virtual SCSI server on either AIX or i5/OS, depending on which model and options you have.
For more information on using virtual devices, including IBM Redbooks and other online resources see: http://publib.boulder.ibm.com/infocenter/eserver/v1r3s/index.jsp?topic=/iphbi/iphbirelated.htm
Additional information on virtualization eServer i5 can be found in the IBM Redbook SG24-6388-01, Implementing POWER Linux on IBM System i Platform. This can be accessed at: http://www.redbooks.ibm.com/redpieces/abstracts/sg246388.html?Open
Once you have your system configured, you need to Activate from the HMC or power it on. Depending on what type of install you are doing, you may need to configure SMS to correctly boot the system into the installation program.

11.3. Do You Have Enough Disk Space?

Nearly every modern-day operating system (OS) uses disk partitions, and Red Hat Enterprise Linux is no exception. When you install Red Hat Enterprise Linux, you may have to work with disk partitions. If you have not worked with disk partitions before (or need a quick review of the basic concepts), refer to Chapter 26, An Introduction to Disk Partitions before proceeding.
The disk space used by Red Hat Enterprise Linux must be separate from the disk space used by other OSes you may have installed on your system.
Before you start the installation process, you must
  • have enough unpartitioned[5] disk space for the installation of Red Hat Enterprise Linux, or
  • have one or more partitions that may be deleted, thereby freeing up enough disk space to install Red Hat Enterprise Linux.
To gain a better sense of how much space you really need, refer to the recommended partitioning sizes discussed in Section 12.19.4, “Recommended Partitioning Scheme”.

11.4. Can You Install Using the CD-ROM or DVD?

Installing from a CD-ROM or DVD requires that you have purchased a Red Hat Enterprise Linux product, you have a Red Hat Enterprise Linux 5.11 CD-ROM or DVD, and you have a DVD/CD-ROM drive on a system that supports booting from it.

11.5. Preparing for a Network Installation

Ensure that you have boot media available on CD, DVD, or a USB storage device such as a flash drive.
The Red Hat Enterprise Linux installation media must be available for either a network installation (via NFS, FTP, or HTTP) or installation via local storage. Use the following steps if you are performing an NFS, FTP, or HTTP installation.
The NFS, FTP, or HTTP server to be used for installation over the network must be a separate machine which can provide the complete contents of the installation DVD-ROM or the installation CD-ROMs.

Note

The Red Hat Enterprise Linux installation program has the ability to test the integrity of the installation media. It works with the CD / DVD, hard drive ISO, and NFS ISO installation methods. Red Hat recommends that you test all installation media before starting the installation process, and before reporting any installation-related bugs (many of the bugs reported are actually due to improperly-burned CDs). To use this test, type the following command at the yaboot: prompt:
	linux mediacheck

Note

In the following examples, the directory on the installation staging server that will contain the installation files will be specified as /location/of/disk/space. The directory that will be made publicly available via FTP, NFS, or HTTP will be specified as /publicly/available/directory. For example, /location/of/disk/space may be a directory you create called /var/isos. /publicly/available/directory might be /var/www/html/rhel5, for an HTTP install.
To copy the files from the installation DVD or CD-ROMs to a Linux machine which acts as an installation staging server, perform the following steps:
  • Create an iso image from the installation disk(s) using the following command (for DVDs):
    dd if=/dev/dvd of=/location/of/disk/space/RHEL5.iso
    where dvd refers to your DVD drive device.

11.5.1. Preparing for FTP and HTTP installation

If you are setting up an installation tree for NFS, FTP, or HTTP installations, you must copy the RELEASE-NOTES files and all files from the RedHat directory on all operating systems ISO images. On Linux and UNIX systems, the following process will properly configure the target directory on your server (repeat for each CD-ROM/ISO image):
  1. Insert CD-ROM or DVD-ROM.
  2. mount /media/cdrom
  3. If you are installing the Server variant, run cp -a /media/cdrom/Server <target-directory>
    If you are installing the Client variant, run cp -a /media/cdrom/Client <target-directory>
  4. cp /media/cdrom/RELEASE-NOTES* <target-directory> (Installation CD 1 or DVD only)
  5. cp /media/cdrom/images <target-directory> (Installation CD 1 or DVD only)
  6. umount /media/cdrom
(Where <target-directory> represents the path to the directory to contain the installation tree.)

Note

Do not copy the Supplementary ISO image, or any of the layered product ISO images, as this will overwrite files necessary for Anaconda's proper operation.
These ISO images must be installed after Red Hat Enterprise Linux has been installed.
Next make sure that the /publicly/available/directory directory is shared via FTP or HTTP, and verify client access. You can check to see whether the directory is accessible from the server itself, and then from another machine on the same subnet that you will be installing to.

11.5.2. Preparing for an NFS install

For NFS installation it is not necessary to mount the iso image. It is sufficient to make the iso image itself available via NFS. You can do this by moving the iso image or images to the NFS exported directory:
  • For DVD:
    mv /location/of/disk/space/RHEL5.iso /publicly/available/directory/
  • For CDROMs:
    mv /location/of/disk/space/disk*.iso /publicly/available/directory/
Ensure that the /publicly/available/directory directory is exported via NFS via an entry in /etc/exports.
To export to a specific system:
/publicly/available/directory client.ip.address
To export to all systems use an entry such as:
/publicly/available/directory *
Start the NFS daemon (on a Red Hat Enterprise Linux system, use /sbin/service nfs start). If NFS is already running, reload the configuration file (on a Red Hat Enterprise Linux system use /sbin/service nfs reload).
Be sure to test the NFS share following the directions in the Red Hat Enterprise Linux Deployment Guide.

11.6. Preparing for a Hard Drive Installation

Note

Hard drive installations only work from ext2, ext3, or FAT file systems. If you have a file system other than those listed here, such as reiserfs, you will not be able to perform a hard drive installation.
Ensure that you have boot media available on CD, DVD, or a USB storage device such as a flash drive.
Hard drive installations require the use of the ISO (or DVD/CD-ROM) images. An ISO image is a file containing an exact copy of a DVD/CD-ROM image. After placing the required ISO images (the binary Red Hat Enterprise Linux DVD/CD-ROMs) in a directory, choose to install from the hard drive. You can then point the installation program at that directory to perform the installation.
To prepare your system for a hard drive installation, you must set the system up in one of the following ways:
  • Using a set of CD-ROMs, or a DVD — Create ISO image files from each installation CD-ROM, or from the DVD. For each CD-ROM (once for the DVD), execute the following command on a Linux system:
    dd if=/dev/cdrom of=/tmp/file-name.iso
  • Using ISO images — transfer these images to the system to be installed.
    Verifying that ISO images are intact before you attempt an installation, helps to avoid problems. To verify the ISO images are intact prior to performing an installation, use an md5sum program (many md5sum programs are available for various operating systems). An md5sum program should be available on the same Linux machine as the ISO images.
Additionally, if a file called updates.img exists in the location from which you install, it is used for updates to anaconda, the installation program. Refer to the file install-methods.txt in the anaconda RPM package for detailed information on the various ways to install Red Hat Enterprise Linux, as well as how to apply the installation program updates.


[5] Unpartitioned disk space means that available disk space on the hard drive(s) you are installing to has not been divided into sections for data. When you partition a disk, each partition behaves like a separate disk drive.

Chapter 12. Installing on IBM System i and IBM System p systems

This chapter explains how to perform a Red Hat Enterprise Linux installation from the DVD/CD-ROM, using the graphical, mouse-based installation program. The following topics are discussed:
  • Becoming familiar with the installation program's user interface
  • Starting the installation program
  • Selecting an installation method
  • Configuration steps during the installation (language, keyboard, mouse, partitioning, etc.)
  • Finishing the installation

12.1. The Graphical Installation Program User Interface

If you have used a graphical user interface (GUI) before, you are already familiar with this process; use your mouse to navigate the screens, click buttons, or enter text fields.
You can also navigate through the installation using the keyboard. The Tab key allows you to move around the screen, the Up and Down arrow keys to scroll through lists, + and - keys expand and collapse lists, while Space and Enter selects or removes from selection a highlighted item. You can also use the Alt+X key command combination as a way of clicking on buttons or making other screen selections, where X is replaced with any underlined letter appearing within that screen.
If you would like to use a graphical installation with a system that does not have that capability, such as a partitioned system, you can use VNC or display forwarding. Both the VNC and display forwarding options require an active network during the installation and the use of boot time arguments. For more information on available boot time options, refer to Chapter 15, Additional Boot Options for IBM Power Systems

Note

If you do not wish to use the GUI installation program, the text mode installation program is also available. To start the text mode installation program, use the following command at the yaboot: prompt:
linux text
Refer to Section 12.5, “The Text Mode Installation Program User Interface” for a brief overview of text mode installation instructions.
It is highly recommended that installs be performed using the GUI installation program. The GUI installation program offers the full functionality of the Red Hat Enterprise Linux installation program, including LVM configuration which is not available during a text mode installation.
Users who must use the text mode installation program can follow the GUI installation instructions and obtain all needed information.

12.2. Booting the IBM System i or IBM System p Installation Program

To boot an IBM System i or IBM System p system from a CD-ROM, you must specify the install boot device in the System Management Services (SMS) menu.
To enter the System Management Services GUI, press the 1 key during the boot process when you hear the chime sound. This brings up a graphical interface similar to the one described in this section.
On a text console, press 1 when the self test is displaying the banner along with the tested components:
SMS console

Figure 12.1. SMS console

Once in the SMS menu, select the option for Select Boot Options. In that menu, specify Select Install or Boot a Device. There, select CD/DVD, and then the bus type (in most cases SCSI). If you are uncertain, you can select to view all devices. This scans all available buses for boot devices, including network adapters and hard drives.
Finally, select the device containing the installation CD. YABOOT is loaded from this device and you are presented with a boot: prompt. Press Enter or wait for the timeout to expire for the installation to begin.
If you are booting via the network, use the images/netboot/ppc64.img file on CD #1.

12.3. A Note about Linux Virtual Consoles

This information only applies to users of non-partitioned System p systems using a video card as their console. Users of partitioned System i and System p systems should skip to Section 12.4, “Using the HMC vterm”.
The Red Hat Enterprise Linux installation program offers more than the dialog boxes of the installation process. Several kinds of diagnostic messages are available to you, as well as a way to enter commands from a shell prompt. The installation program displays these messages on five virtual consoles, among which you can switch using a single keystroke combination.
A virtual console is a shell prompt in a non-graphical environment, accessed from the physical machine, not remotely. Multiple virtual consoles can be accessed simultaneously.
These virtual consoles can be helpful if you encounter a problem while installing Red Hat Enterprise Linux. Messages displayed on the installation or system consoles can help pinpoint a problem. Refer to Table 12.1, “Console, Keystrokes, and Contents” for a listing of the virtual consoles, keystrokes used to switch to them, and their contents.
Generally, there is no reason to leave the default console (virtual console #6) for graphical installations unless you are attempting to diagnose installation problems.

Table 12.1. Console, Keystrokes, and Contents

console keystrokes contents
1 ctrl+alt+f1 installation dialog
2 ctrl+alt+f2 shell prompt
3 ctrl+alt+f3 install log (messages from installation program)
4 ctrl+alt+f4 system-related messages
5 ctrl+alt+f5 other messages
6 ctrl+alt+f6 x graphical display

12.4. Using the HMC vterm

The HMC vterm is the console for any partitioned IBM System p or IBM System i system. This is opened by right clicking on the partition on the HMC, and then selecting Open Terminal Window. Only a single vterm can be connected to the console at one time and there is no console access for partitioned system besides the vterm. This often is referred to as a 'virtual console', but is different from the virtual consoles in Section 12.3, “A Note about Linux Virtual Consoles” .

12.5. The Text Mode Installation Program User Interface

The Red Hat Enterprise Linux text mode installation program uses a screen-based interface that includes most of the on-screen widgets commonly found on graphical user interfaces. Figure 12.2, “Installation Program Widgets as seen in Boot Loader Configuration, and Figure 12.3, “Installation Program Widgets as seen in Disk Druid, illustrate the screens that appear during the installation process.

Note

While text mode installations are not explicitly documented, those using the text mode installation program can easily follow the GUI installation instructions. One thing to note is that manipulation of LVM (Logical Volume Management) disk volumes is only possible in graphical mode. In text mode it is only possible to view and accept the default LVM setup.
Installation Program Widgets as seen in Boot Loader Configuration

Figure 12.2. Installation Program Widgets as seen in Boot Loader Configuration

Installation Program Widgets as seen in Disk Druid

Figure 12.3. Installation Program Widgets as seen in Disk Druid

  • Window — Windows (usually referred to as dialogs in this manual) appear on your screen throughout the installation process. At times, one window may overlay another; in these cases, you can only interact with the window on top. When you are finished in that window, it disappears, allowing you to continue working in the window underneath.
  • Checkbox — Checkboxes allow you to select or deselect a feature. The box displays either an asterisk (selected) or a space (unselected). When the cursor is within a checkbox, press Space to select or deselect a feature.
  • Text Input — Text input lines are regions where you can enter information required by the installation program. When the cursor rests on a text input line, you may enter and/or edit information on that line.
  • Text Widget — Text widgets are regions of the screen for the display of text. At times, text widgets may also contain other widgets, such as checkboxes. If a text widget contains more information than can be displayed in the space reserved for it, a scroll bar appears; if you position the cursor within the text widget, you can then use the Up and Down arrow keys to scroll through all the information available. Your current position is shown on the scroll bar by a # character, which moves up and down the scroll bar as you scroll.
  • Scroll Bar — Scroll bars appear on the side or bottom of a window to control which part of a list or document is currently in the window's frame. The scroll bar makes it easy to move to any part of a file.
  • Button Widget — Button widgets are the primary method of interacting with the installation program. You progress through the windows of the installation program by navigating these buttons, using the Tab and Enter keys. Buttons can be selected when they are highlighted.
  • Cursor — Although not a widget, the cursor is used to select (and interact with) a particular widget. As the cursor is moved from widget to widget, it may cause the widget to change color, or the cursor itself may only appear positioned in or next to the widget. In Figure 12.2, “Installation Program Widgets as seen in Boot Loader Configuration, the cursor is positioned on the OK button. Figure 12.3, “Installation Program Widgets as seen in Disk Druid, shows the cursor on the Edit button.

12.5.1. Using the Keyboard to Navigate

Navigation through the installation dialogs is performed through a simple set of keystrokes. To move the cursor, use the Left, Right, Up, and Down arrow keys. Use Tab, and Shift-Tab to cycle forward or backward through each widget on the screen. Along the bottom, most screens display a summary of available cursor positioning keys.
To "press" a button, position the cursor over the button (using Tab, for example) and press Space or Enter. To select an item from a list of items, move the cursor to the item you wish to select and press Enter. To select an item with a checkbox, move the cursor to the checkbox and press Space to select an item. To deselect, press Space a second time.
Pressing F12 accepts the current values and proceeds to the next dialog; it is equivalent to pressing the OK button.

Warning

Unless a dialog box is waiting for your input, do not press any keys during the installation process (doing so may result in unpredictable behavior).

12.6.  Beginning Installation

12.6.1. Installing from DVD/CD-ROM

To install Red Hat Enterprise Linux from a DVD/CD-ROM, place the DVD or CD #1 in your DVD/CD-ROM drive and boot your system from the DVD/CD-ROM.
The installation program then probes your system and attempts to identify your CD-ROM drive. It starts by looking for an IDE (also known as an ATAPI) CD-ROM drive.
If your CD-ROM drive is not detected, and it is a SCSI CD-ROM, the installation program prompts you to choose a SCSI driver. Choose the driver that most closely resembles your adapter. You may specify options for the driver if necessary; however, most drivers detect your SCSI adapter automatically.
If the DVD/CD-ROM drive is found and the driver loaded, the installer will present you with the option to perform a media check on the DVD/CD-ROM. This will take some time, and you may opt to skip over this step. However, if you later encounter problems with the installer, you should reboot and perform the media check before calling for support. From the media check dialog, continue to the next stage of the installation process (refer to Section 12.12, “Welcome to Red Hat Enterprise Linux”).

12.7. Installing from a Hard Drive

The Select Partition screen applies only if you are installing from a disk partition (that is, if you used the askmethod boot options and selected Hard Drive in the Installation Method dialog). This dialog allows you to name the disk partition and directory from which you are installing Red Hat Enterprise Linux. If you used the repo=hd boot option, you already specified a partition.
Selecting Partition Dialog for Hard Drive Installation

Figure 12.4. Selecting Partition Dialog for Hard Drive Installation

Enter the device name of the partition containing the Red Hat Enterprise Linux ISO images. This partition must be formatted with a ext2 or vfat filesystem, and cannot be a logical volume. There is also a field labeled Directory holding images.
If the ISO images are in the root (top-level) directory of a partition, enter a /. If the ISO images are located in a subdirectory of a mounted partition, enter the name of the directory holding the ISO images within that partition. For example, if the partition on which the ISO images is normally mounted as /home/, and the images are in /home/new/, you would enter /new/.
After you have identified the disk partition, the Welcome dialog appears.

12.8. Performing a Network Installation

If you are performing a network installation and booted with the askmethod boot option, the Configure TCP/IP dialog appears. This dialog asks for your IP and other network addresses. You can choose to configure the IP address and Netmask of the device via DHCP or manually. If manually, you have the option to enter IPv4 and/or IPv6 information. Enter the IP address you are using during installation and press Enter. Note that you need to supply IPv4 information if you wish to perform an NFS installation.
TCP/IP Configuration

Figure 12.5. TCP/IP Configuration

12.9. Installing via NFS

The NFS dialog applies only if you are installing from an NFS server (if you selected NFS Image in the Installation Method dialog).
Enter the domain name or IP address of your NFS server. For example, if you are installing from a host named eastcoast in the domain example.com, enter eastcoast.example.com in the NFS Server field.
Next, enter the name of the exported directory. If you followed the setup described in Section 11.5, “Preparing for a Network Installation”, you would enter the directory /export/directory/ which contains the variant/ directory.
If the NFS server is exporting a mirror of the Red Hat Enterprise Linux installation tree, enter the directory which contains the root of the installation tree. You will enter an Installation Key later on in the process which will determine which subdirectories are used to install from. If everything was specified properly, a message appears indicating that the installation program for Red Hat Enterprise Linux is running.
NFS Setup Dialog

Figure 12.6. NFS Setup Dialog

If the NFS server is exporting the ISO images of the Red Hat Enterprise Linux CD-ROMs, enter the directory which contains the ISO images.
Next, the Welcome dialog appears.

12.10. Installing via FTP

The FTP dialog applies only if you are installing from an FTP server (that is, if you used the askmethod boot options and selected FTP in the Installation Method dialog). This dialog allows you to identify the FTP server from which you are installing Red Hat Enterprise Linux. If you used the repo=ftp boot option, you already specified a server and path.
FTP Setup Dialog

Figure 12.7. FTP Setup Dialog

Enter the name or IP address of the FTP site you are installing from, and the name of the directory containing the variant/ directory for your architecture. For example, if the FTP site contains the directory /mirrors/redhat/arch/variant;/, enter /mirrors/redhat/arch/ (where arch is replaced with the architecture type of your system, such as i386, ia64, ppc, or s390x, and variant is the variant that you are installing, such as Client, Server, Workstation, etc.). If everything was specified properly, a message box appears indicating that files are being retrieved from the server.
Next, the Welcome dialog appears.

Note

You can save disk space by using the ISO images you have already copied to the server. To accomplish this, install Red Hat Enterprise Linux using ISO images without copying them into a single tree by loopback mounting them. For each ISO image:
mkdir discX
mount -o loop RHEL5-discX.iso discX
Replace X with the corresponding disc number.

12.11. Installing via HTTP

The HTTP dialog applies only if you are installing from an HTTP server (that is, if you used the askmethod boot option and selected HTTP in the Installation Method dialog). This dialog prompts you for information about the HTTP server from which you are installing Red Hat Enterprise Linux. If you used the repo=http boot option, you already specified a server and path.
Enter the name or IP address of the HTTP site you are installing from, and the name of the directory containing the variant/ directory for your architecture. For example, if the HTTP site contains the directory /mirrors/redhat/arch/variant/, enter /mirrors/redhat/arch/ (where arch is replaced with the architecture type of your system, such as i386, ia64, ppc, or s390x, and variant is the variant that you are installing, such as Client, Server, Workstation, etc.). If everything was specified properly, a message box appears indicating that files are being retrieved from the server.
HTTP Setup Dialog

Figure 12.8. HTTP Setup Dialog

Next, the Welcome dialog appears.

Note

You can save disk space by using the ISO images you have already copied to the server. To accomplish this, install Red Hat Enterprise Linux using ISO images without copying them into a single tree by loopback mounting them. For each ISO image:
mkdir discX
mount -o loop RHEL5-discX.iso discX
Replace X with the corresponding disc number.

12.12. Welcome to Red Hat Enterprise Linux

The Welcome screen does not prompt you for any input. From this screen you can access the Release Notes for Red Hat Enterprise Linux 5.11 by clicking on the Release Notes button.
Click on the Next button to continue.

12.13. Language Selection

Using your mouse, select a language to use for the installation (refer to Figure 12.9, “Language Selection”).
The language you select here will become the default language for the operating system once it is installed. Selecting the appropriate language also helps target your time zone configuration later in the installation. The installation program tries to define the appropriate time zone based on what you specify on this screen.
Language Selection

Figure 12.9. Language Selection

Once you select the appropriate language, click Next to continue.

12.14. Keyboard Configuration

Using your mouse, select the correct layout type (for example, U.S. English) for the keyboard you would prefer to use for the installation and as the system default (refer to Figure 12.10, “Keyboard Configuration”).
Once you have made your selection, click Next to continue.
Keyboard Configuration

Figure 12.10. Keyboard Configuration

Note

To change your keyboard layout type after you have completed the installation, use the Keyboard Configuration Tool.
Type the system-config-keyboard command in a shell prompt to launch the Keyboard Configuration Tool. If you are not root, it prompts you for the root password to continue.

12.15. Enter the Installation Number

Enter your Installation Number (refer to Figure 12.11, “Installation Number”). This number will determine the package selection set that is available to the installer. If you choose to skip entering the installation number you will be presented with a basic selection of packages to install later on.
Installation Number

Figure 12.11. Installation Number

12.16. Disk Partitioning Setup

Partitioning allows you to divide your hard drive into isolated sections, where each section behaves as its own hard drive. Partitioning is particularly useful if you run multiple operating systems. If you are not sure how you want your system to be partitioned, read Chapter 26, An Introduction to Disk Partitions for more information.
On this screen you can choose to create the default layout or choose to manual partition using the 'Create custom layout' option of Disk Druid.
The first three options allow you to perform an automated installation without having to partition your drive(s) yourself. If you do not feel comfortable with partitioning your system, it is recommended that you do not choose to create a custom layout and instead let the installation program partition for you.
You can configure an iSCSI target for installation, or disable a dmraid device from this screen by clicking on the 'Advanced storage configuration' button. For more information refer to Section 12.17, “ Advanced Storage Options ”.

Warning

The Update Agent downloads updated packages to /var/cache/yum/ by default. If you partition the system manually, and create a separate /var/ partition, be sure to create the partition large enough (3.0 GB or more) to download package updates.
Disk Partitioning Setup

Figure 12.12. Disk Partitioning Setup

If you choose to create a custom layout using Disk Druid, refer to Section 12.19, “Partitioning Your System”.

Warning

If you receive an error after the Disk Partitioning Setup phase of the installation saying something similar to:
"The partition table on device hda was unreadable. To create new partitions it must be initialized, causing the loss of ALL DATA on this drive."
No matter what type of installation you are performing, backups of the existing data on your systems should always be made.

Important

To install Red Hat Enterprise Linux on a network device accessible through multiple paths, deselect all local storage in the Select the drive(s) to use for this installation window, and select a device labeled mapper/mpath instead.
Note that migrating the root file system of an existing Red Hat Enterprise Linux installation from single path storage to multipath storage is not supported. You must perform a new installation to move the root file system to a multipath storage device. Therefore you should plan your installation accordingly. See https://access.redhat.com/site/solutions/66501 for more information.

12.17.  Advanced Storage Options

Advanced Storage Options

Figure 12.13. Advanced Storage Options

From this screen you can choose to disable a dmraid device, in which case the individual elements of the dmraid device will appear as separate hard drives. You can also choose to configure an iSCSI (SCSI over TCP/IP) target.
To configure an ISCSI target invoke the Configure ISCSI Parameters dialog by selecting Add ISCSI target and clicking on the Add Drive button. If a network connection is not already active, the installer prompts you to provide details of your network interface. Select your network interface from the drop-down menu, then either leave the Use dynamic IP configuration box checked, or uncheck it to enter the IP address of your system and the IP addresses of the gateway and nameserver on your network. Ensure that the Enable IPv4 box remains checked.
Enable network Interface

Figure 12.14. Enable network Interface

Fill in the details for the iSCSI target IP and provide a unique iSCSI initiator name to identify this system. If the iSCSI target uses Challenge Handshake Authentication Protocol (CHAP) for authentication, enter the CHAP username and password. If your environment uses 2-way CHAP (also called "Mutual CHAP"), also enter the reverse CHAP username and password. Click the Add target button to attempt connection to the ISCSI target using this information.
Configure ISCSI Parameters

Figure 12.15. Configure ISCSI Parameters

Please note that you will be able to reattempt with a different ISCSI target IP should you enter it incorrectly, but in order to change the ISCSI initiator name you will need to restart the installation.

12.18. Create Default Layout

Create default layout allows you to have some control concerning what data is removed (if any) from your system. Your options are:
  • Remove all partitions on selected drives and create default layout — select this option to remove all partitions on your hard drive(s) (this includes partitions created by other operating systems such as Windows VFAT or NTFS partitions).

    Warning

    If you select this option, all data on the selected hard drive(s) is removed by the installation program. Do not select this option if you have information that you want to keep on the hard drive(s) where you are installing Red Hat Enterprise Linux.
  • Remove Linux partitions on selected drives and create default layout — select this option to remove only Linux partitions (partitions created from a previous Linux installation). This does not remove other partitions you may have on your hard drive(s) (such as VFAT or FAT32 partitions).
  • Use free space on selected drives and create default layout — select this option to retain your current data and partitions, assuming you have enough free space available on your hard drive(s).
Create Default Layout

Figure 12.16. Create Default Layout

Using your mouse, choose the storage drive(s) on which you want Red Hat Enterprise Linux to be installed. If you have two or more drives, you can choose which drive(s) should contain this installation. Unselected drives, and any data on them, are not touched.

Warning

It is always a good idea to back up any data that you have on your systems. For example, if you are upgrading or creating a dual-boot system, you should back up any data you wish to keep on your drive(s). Mistakes do happen and can result in the loss of all your data.

Note

[This text does not apply to iSeries system users.]
If you have a RAID card, be aware that some BIOSes do not support booting from the RAID card. In cases such as these, the /boot/ partition must be created on a partition outside of the RAID array, such as on a separate hard drive. An internal hard drive is necessary to use for partition creation with problematic RAID cards.
A /boot/ partition is also necessary for software RAID setups.
If you have chosen to automatically partition your system, you should select Review and manually edit your /boot/ partition.
To review and make any necessary changes to the partitions created by automatic partitioning, select the Review option. After selecting Review and clicking Next to move forward, the partitions created for you in Disk Druid appear. You can make modifications to these partitions if they do not meet your needs.
Click Next once you have made your selections to proceed.

12.19. Partitioning Your System

If you chose one of the three automatic partitioning options and did not select Review, skip ahead to Section 12.20, “Network Configuration”.
If you chose one of the automatic partitioning options and selected Review, you can either accept the current partition settings (click Next), or modify the setup using Disk Druid, the manual partitioning tool.

Note

Please note that in the text mode installation it is not possible to work with LVM (Logical Volumes) beyond viewing the existing setup. LVM can only be set up using the graphical Disk Druid program in a graphical installation.
If you chose to create a custom layout, you must tell the installation program where to install Red Hat Enterprise Linux. This is done by defining mount points for one or more disk partitions in which Red Hat Enterprise Linux is installed.

Note

If you have not yet planned how to set up your partitions, refer to Chapter 26, An Introduction to Disk Partitions and Section 12.19.4, “Recommended Partitioning Scheme”. At a bare minimum, you need an appropriately-sized root (/) partition, a /boot/ partition, PPC PReP boot partition, and a swap partition equal to twice the amount of RAM you have on the system.
Partitioning with Disk Druid on IBM System p and System i systems

Figure 12.17. Partitioning with Disk Druid on IBM System p and System i systems

The partitioning tool used by the installation program is Disk Druid. With the exception of certain esoteric situations, Disk Druid can handle the partitioning requirements for a typical installation.

12.19.1. Graphical Display of Hard Drive(s)

Disk Druid offers a graphical representation of your hard drive(s).
Using your mouse, click once to highlight a particular field in the graphical display. Double-click to edit an existing partition or to create a partition out of existing free space.
Above the display, you can review the name of the drive (such as /dev/hda), its size (in MB), and its model as detected by the installation program.

12.19.2. Disk Druid's Buttons

These buttons control Disk Druid's actions. They are used to change the attributes of a partition (for example the file system type and mount point) and also to create RAID devices. Buttons on this screen are also used to accept the changes you have made, or to exit Disk Druid. For further explanation, take a look at each button in order:
  • New: Used to request a new partition. When selected, a dialog box appears containing fields (such as the mount point and size fields) that must be filled in.
  • Edit: Used to modify attributes of the partition currently selected in the Partitions section. Selecting Edit opens a dialog box. Some or all of the fields can be edited, depending on whether the partition information has already been written to disk.
    You can also edit free space as represented in the graphical display to create a new partition within that space. Either highlight the free space and then select the Edit button, or double-click on the free space to edit it.
  • To make a RAID device, you must first create (or reuse existing) software RAID partitions. Once you have created two or more software RAID partitions, select Make RAID to join the software RAID partitions into a RAID device.
  • Delete: Used to remove the partition currently highlighted in the Current Disk Partitions section. You will be asked to confirm the deletion of any partition.
  • Reset: Used to restore Disk Druid to its original state. All changes made will be lost if you Reset the partitions.
  • RAID: Used to provide redundancy to any or all disk partitions. It should only be used if you have experience using RAID. To read more about RAID, see the Red Hat Enterprise Linux Deployment Guide.
    To make a RAID device, you must first create software RAID partitions. Once you have created two or more software RAID partitions, select RAID to join the software RAID partitions into a RAID device.
  • LVM: Allows you to create an LVM logical volume. The role of LVM (Logical Volume Manager) is to present a simple logical view of underlying physical storage space, such as a hard drive(s). LVM manages individual physical disks — or to be more precise, the individual partitions present on them. It should only be used if you have experience using LVM. To read more about LVM, see the Red Hat Enterprise Linux Deployment Guide. Note, LVM is only available in the graphical installation program.
    To create an LVM logical volume, you must first create partitions of type physical volume (LVM). Once you have created one or more physical volume (LVM) partitions, select LVM to create an LVM logical volume.

12.19.3. Partition Fields

Above the partition hierarchy are labels which present information about the partitions you are creating. The labels are defined as follows:
  • Device: This field displays the partition's device name.
  • Mount Point/RAID/Volume: A mount point is the location within the directory hierarchy at which a volume exists; the volume is "mounted" at this location. This field indicates where the partition is mounted. If a partition exists, but is not set, then you need to define its mount point. Double-click on the partition or click the Edit button.
  • Type: This field shows the partition's file system type (for example, ext2, ext3, or vfat).
  • Format: This field shows if the partition being created will be formatted.
  • Size (MB): This field shows the partition's size (in MB).
  • Start: This field shows the cylinder on your hard drive where the partition begins.
  • End: This field shows the cylinder on your hard drive where the partition ends.
Hide RAID device/LVM Volume Group members: Select this option if you do not want to view any RAID device or LVM Volume Group members that have been created.

12.19.4. Recommended Partitioning Scheme

Unless you have a reason for doing otherwise, we recommend that you create the following partitions:
  • A swap partition (at least 256 MB) — swap partitions are used to support virtual memory. In other words, data is written to a swap partition when there is not enough RAM to store the data your system is processing.
    In years past, the recommended amount of swap space increased linearly with the amount of RAM in the system. But because the amount of memory in modern systems has increased into the hundreds of gigabytes, it is now recognized that the amount of swap space that a system needs is a function of the memory workload running on that system. However, given that swap space is usually designated at install time, and that it can be difficult to determine beforehand the memory workload of a system, we recommend determining system swap using the following table.

    Table 12.2. Recommended System Swap Space

    Amount of RAM in the System Recommended Amount of Swap Space
    4GB of RAM or less a minimum of 2GB of swap space
    4GB to 16GB of RAM a minimum of 4GB of swap space
    16GB to 64GB of RAM a minimum of 8GB of swap space
    64GB to 256GB of RAM a minimum of 16GB of swap space
    256GB to 512GB of RAM a minimum of 32GB of swap space
    Note that you can obtain better performance by distributing swap space over multiple storage devices, particularly on systems with fast drives, controllers, and interfaces.
  • A PPC PReP boot partition on the first partition of the hard drive — the PPC PReP boot partition contains the YABOOT boot loader (which allows other POWER systems to boot Red Hat Enterprise Linux). Unless you plan to boot from a floppy or network source, you must have a PPC PReP boot partition to boot Red Hat Enterprise Linux.
    For IBM System i and IBM System p users: The PPC PReP boot partition should be between 4-8 MB, not to exceed 10 MB.
  • A /boot/ partition (100 MB) — the partition mounted on /boot/ contains the operating system kernel (which allows your system to boot Red Hat Enterprise Linux), along with files used during the bootstrap process. Due to the limitations of most PC firmware, creating a small partition to hold these is a good idea. For most users, a 100 MB boot partition is sufficient.

    Warning

    If you have a RAID card, be aware that Red Hat Enterprise Linux 5.11 does not support setting up hardware RAID on an IPR card. You can boot the standalone diagnostics CD prior to installation to create a RAID array and then install to that RAID array.
  • A root partition (3.0 GB - 5.0 GB) — this is where "/" (the root directory) is located. In this setup, all files (except those stored in /boot) are on the root partition.
    A 3.0 GB partition allows you to install a minimal installation, while a 5.0 GB root partition lets you perform a full installation, choosing all package groups.

Warning

Red Hat Enterprise Linux 5.11 does not support having a separate /var on a network filesystem (for example, NFS, iSCSI, or NBD) The /var directory contains critical data that must be read from or written to during the boot process before establishing network services.
However, you may have /var/spool, /var/www or other subdirectories on a separate network disk, just not the complete /var filesystem.

12.19.5. Adding Partitions

To add a new partition, select the New button. A dialog box appears (refer to Figure 12.18, “Creating a New Partition”).

Note

You must dedicate at least one partition for this installation, and optionally more. For more information, refer to Chapter 26, An Introduction to Disk Partitions.
Creating a New Partition

Figure 12.18. Creating a New Partition

  • Mount Point: Enter the partition's mount point. For example, if this partition should be the root partition, enter /; enter /boot for the /boot partition, and so on. You can also use the pull-down menu to choose the correct mount point for your partition. For a swap partition the mount point should not be set - setting the filesystem type to swap is sufficient.
  • File System Type: Using the pull-down menu, select the appropriate file system type for this partition. For more information on file system types, refer to Section 12.19.5.1, “File System Types”.
  • Allowable Drives: This field contains a list of the hard disks installed on your system. If a hard disk's box is highlighted, then a desired partition can be created on that hard disk. If the box is not checked, then the partition will never be created on that hard disk. By using different checkbox settings, you can have Disk Druid place partitions where you need them, or let Disk Druid decide where partitions should go.
  • Size (MB): Enter the size (in megabytes) of the partition. Note, this field starts with 100 MB; unless changed, only a 100 MB partition will be created.
  • Additional Size Options: Choose whether to keep this partition at a fixed size, to allow it to "grow" (fill up the available hard drive space) to a certain point, or to allow it to grow to fill any remaining hard drive space available.
    If you choose Fill all space up to (MB), you must give size constraints in the field to the right of this option. This allows you to keep a certain amount of space free on your hard drive for future use.
  • Force to be a primary partition: Select whether the partition you are creating should be one of the first four partitions on the hard drive. If unselected, the partition is created as a logical partition. Refer to Section 26.1.3, “Partitions within Partitions — An Overview of Extended Partitions”, for more information.
  • Encrypt: Choose whether to encrypt the partition so that the data stored on it cannot be accessed without a passphrase, even if the storage device is connected to another system. Refer to Chapter 29, Disk Encryption Guide for information on encryption of storage devices. If you select this option, the installer prompts you to provide a passphrase before it writes the partition to the disk.
  • OK: Select OK once you are satisfied with the settings and wish to create the partition.
  • Cancel: Select Cancel if you do not want to create the partition.

12.19.5.1. File System Types

Red Hat Enterprise Linux allows you to create different partition types, based on the file system they will use. The following is a brief description of the different file systems available, and how they can be utilized.
  • ext3 — The ext3 file system is based on the ext2 file system and has one main advantage — journaling. Using a journaling file system reduces time spent recovering a file system after a crash as there is no need to fsck [6] the file system. A maximum file system size of 16TB is supported for ext3. The ext3 file system is selected by default and is highly recommended.
  • ext2 — An ext2 file system supports standard Unix file types (regular files, directories, symbolic links, etc). It provides the ability to assign long file names, up to 255 characters.
  • physical volume (LVM) — Creating one or more physical volume (LVM) partitions allows you to create an LVM logical volume. LVM can improve performance when using physical disks. For more information regarding LVM, see the Red Hat Enterprise Linux Deployment Guide.
  • software RAID — Creating two or more software RAID partitions allows you to create a RAID device. For more information regarding RAID, see chapter RAID (Redundant Array of Independent Disks) in the Red Hat Enterprise Linux Deployment Guide.
  • swap — Swap partitions are used to support virtual memory. In other words, data is written to a swap partition when there is not enough RAM to store the data your system is processing. See the Red Hat Enterprise Linux Deployment Guide for additional information.

12.19.6. Editing Partitions

To edit a partition, select the Edit button or double-click on the existing partition.

Note

If the partition already exists on your disk, you can only change the partition's mount point. To make any other changes, you must delete the partition and recreate it.

12.20. Network Configuration

If you do not have a network device, physical LAN, or virtual LAN, this screen does not appear during your installation and you should advance to Section 12.21, “Time Zone Configuration”.
Network Configuration

Figure 12.19. Network Configuration

The installation program automatically detects any network devices you have and displays them in the Network Devices list.
When you have selected a network device, click Edit. From the Edit Interface dialog, you can choose to configure the IP address and Netmask (for IPv4 - Prefix for IPv6) of the device to use DHCP or to use static settings. If you do not have DHCP client access or you are unsure what to provide here, contact your network administrator.
Editing a Network Device

Figure 12.20. Editing a Network Device

Note

Do not use the numbers as seen in this sample configuration. These values will not work for your own network configuration. If you are not sure what values to enter, contact your network administrator for assistance.
If you have a hostname (fully qualified domain name) for the network device, you can choose to have DHCP (Dynamic Host Configuration Protocol) automatically detect it or you can manually enter the hostname in the field provided.
Finally, if you entered the IP and Netmask information manually, you may also enter the Gateway address and the Primary and Secondary DNS addresses.

Note

To change your network configuration after you have completed the installation, use the Network Administration Tool.
Type the system-config-network command in a shell prompt to launch the Network Administration Tool. If you are not root, it prompts you for the root password to continue.

12.21. Time Zone Configuration

Set your time zone by selecting the city closest to your computer's physical location. Click on the map to zoom in to a particular geographical region of the world.
From here there are two ways for you to select your time zone:
  • Using your mouse, click on the interactive map to select a specific city (represented by a yellow dot). A red X appears indicating your selection.
  • You can also scroll through the list at the bottom of the screen to select your time zone. Using your mouse, click on a location to highlight your selection.
Configuring the Time Zone

Figure 12.21. Configuring the Time Zone

Select System Clock uses UTC if you know that your system is set to UTC.

Note

To change your time zone configuration after you have completed the installation, use the Time and Date Properties Tool.
Type the system-config-date command in a shell prompt to launch the Time and Date Properties Tool. If you are not root, it prompts you for the root password to continue.
To run the Time and Date Properties Tool as a text-based application, use the command timeconfig.

12.22. Set Root Password

Setting up a root account and password is one of the most important steps during your installation. Your root account is similar to the administrator account used on Windows NT machines. The root account is used to install packages, upgrade RPMs, and perform most system maintenance. Logging in as root gives you complete control over your system.

Note

The root user (also known as the superuser) has complete access to the entire system; for this reason, logging in as the root user is best done only to perform system maintenance or administration.
Root Password

Figure 12.22. Root Password

Use the root account only for system administration. Create a non-root account for your general use and su - to root when you need to fix something quickly. These basic rules minimize the chances of a typo or an incorrect command doing damage to your system.

Note

To become root, type su - at the shell prompt in a terminal window and then press Enter. Then, enter the root password and press Enter.
The installation program prompts you to set a root password[7] for your system. You cannot proceed to the next stage of the installation process without entering a root password.
The root password must be at least six characters long; the password you type is not echoed to the screen. You must enter the password twice; if the two passwords do not match, the installation program asks you to enter them again.
You should make the root password something you can remember, but not something that is easy for someone else to guess. Your name, your phone number, qwerty, password, root, 123456, and anteater are all examples of bad passwords. Good passwords mix numerals with upper and lower case letters and do not contain dictionary words: Aard387vark or 420BMttNT, for example. Remember that the password is case-sensitive. If you write down your password, keep it in a secure place. However, it is recommended that you do not write down this or any password you create.

Note

Do not use one of the example passwords offered in this manual. Using one of these passwords could be considered a security risk.

Note

To change your root password after you have completed the installation, use the Root Password Tool.
Type the system-config-rootpassword command in a shell prompt to launch the Root Password Tool. If you are not root, it prompts you for the root password to continue.

12.23. Package Group Selection

Now that you have made most of the choices for your installation, you are ready to confirm the default package selection or customize packages for your system.
The Package Installation Defaults screen appears and details the default package set for your Red Hat Enterprise Linux installation. This screen varies depending on the version of Red Hat Enterprise Linux you are installing.
If you choose to accept the current package list, skip ahead to Section 12.24, “Preparing to Install”.
To customize your package set further, select the Customize now option on the screen. Clicking Next takes you to the Package Group Selection screen.
You can select package groups, which group components together according to function (for example, X Window System and Editors), individual packages, or a combination of the two.

Note

Users who want support for developing or running 64-bit applications are encouraged to select the Compatibility Arch Support and Compatibility Arch Development Support packages to install architecture specific support for their systems.
To select a component, click on the checkbox beside it (refer to Figure 12.23, “Package Group Selection”).
Package Group Selection

Figure 12.23. Package Group Selection

Select each component you wish to install.
Once a package group has been selected, if optional components are available you can click on Optional packages to view which packages are installed by default, and to add or remove optional packages from that group. If there are no optional components this button will be disabled.
Package Group Details

Figure 12.24. Package Group Details

12.24. Preparing to Install

12.24.1.  Prepare to Install

A screen preparing you for the installation of Red Hat Enterprise Linux now appears.
For your reference, a complete log of your installation can be found in /root/install.log once you reboot your system.

Warning

If, for some reason, you would rather not continue with the installation process, this is your last opportunity to safely cancel the process and reboot your machine. Once you press the Next button, partitions are written and packages are installed. If you wish to abort the installation, you should reboot now before any existing information on any hard drive is rewritten.
To cancel this installation process, press your computer's Reset button or use the Control+Alt+Delete key combination to restart your machine.

12.25. Installing Packages

At this point there is nothing left for you to do until all the packages have been installed. How quickly this happens depends on the number of packages you have selected and your computer's speed.

12.26. Installation Complete

Congratulations! Your Red Hat Enterprise Linux installation is now complete!
The installation program prompts you to prepare your system for reboot.
IBM eServer System p and System i — Completing the Installation
Do not forget to remove any boot media.
After rebooting, you must set the open firmware boot device to the disk containing your Red Hat Enterprise Linux PReP and / partitions. To accomplish this, wait until the LED indicator or HMC SRC says E1F1, then press 1 to enter the System Management Services GUI. Click on Select Boot Options. Select Select Boot Devices. Select Configure 1st Boot Device. Select the disk containing Red Hat Enterprise Linux. Set the other devices as you wish. Then exit the SMS menus to boot your new system.

Note

Steps in the SMS menu may be different depending on the machine model.
After your computer's normal power-up sequence has completed, YABOOT's prompt appears, at which you can do any of the following things:
  • Press Enter — causes YABOOT's default boot entry to be booted.
  • Select a boot label, followed by Enter — causes YABOOT to boot the operating system corresponding to the boot label. (Press Tab for non-System i systems at the boot: prompt for a list of valid boot labels.)
  • Do nothing — after YABOOT's timeout period, (by default, five seconds) YABOOT automatically boots the default boot entry.
Once Red Hat Enterprise Linux has booted, one or more screens of messages should scroll by. Eventually, a login: prompt or a GUI login screen (if you installed the X Window System and chose to start X automatically) appears.
The first time you start your Red Hat Enterprise Linux system in run level 5 (the graphical run level), the Setup Agent is presented, which guides you through the Red Hat Enterprise Linux configuration. Using this tool, you can set your system time and date, install software, register your machine with Red Hat Network, and more. The Setup Agent lets you configure your environment at the beginning, so that you can get started using your Red Hat Enterprise Linux system quickly.
For information on registering your Red Hat Enterprise Linux subscription, refer to Chapter 25, Register Your System and Apply Subscriptions.


[6] The fsck application is used to check the file system for metadata consistency and optionally repair one or more Linux file systems.
[7] A root password is the administrative password for your Red Hat Enterprise Linux system. You should only log in as root when needed for system maintenance. The root account does not operate within the restrictions placed on normal user accounts, so changes made as root can have implications for your entire system.

Chapter 13. Updating drivers during installation on IBM POWER systems

In most cases, Red Hat Enterprise Linux already includes drivers for the devices that make up your system. However, if your system contains hardware that has been released very recently, drivers for this hardware might not yet be included. Sometimes, a driver update that provides support for a new device might be available from Red Hat or your hardware vendor as a ISO image file or a rpm package. Both these formats supply all the files that make up the driver update together in a single file.
Often, you do not need the new hardware during the installation process. For example, if you use a DVD to install to a local hard drive, the installation will succeed even if drivers for your network card are not available. In situations like this, complete the installation and add support for the piece of hardware afterward — refer to Section 23.1, “Driver update rpm packages” for details of using a driver update rpm package to add this support.
In other situations, you might want to add drivers for a device during the installation process to support a particular configuration. For example, you might want to install drivers for a network device or a storage adapter card to give the installer access to the storage devices that your system uses. You can use a driver update image file to add this support during installation in one of three ways:
  1. place the image file in a location accessible to the installer:
    1. on a local IDE hard drive
    2. a USB storage device such as a USB flash drive
    3. on a FTP, HTTP, or NFS server on your local network (or take note of a location on the Internet where someone else has placed the image file)
  2. create a driver update disk by unpacking the image file onto:
    1. a CD (if your computer has an IDE optical drive)
    2. a DVD (if your computer has an IDE optical drive)
    3. a floppy disk
    4. a USB storage device such as a USB flash drive
  3. create an initial ramdisk update from the image file and store it on a PXE server. This is an advanced procedure that you should consider only if you cannot perform a driver update with any other method.
If Red Hat, your hardware vendor, or a trusted third party told you that you will require a driver update during the installation process, choose a method to supply the update from the methods described in this chapter and test it before beginning the installation. Conversely, do not perform a driver update during installation unless you are certain that your system requires it. Although installing an unnecessary driver update will not cause harm, the presence of a driver on a system for which it was not intended can complicate support.

13.1. Limitations of driver updates during installation

Unfortunately, some situations persist in which you cannot use a driver update to provide drivers during installation:
Devices already in use
You cannot use a driver update to replace drivers that the installation program has already loaded. Instead, you must complete the installation with the drivers that the installation program loaded and update to the new drivers after installation, or, if you need the new drivers for the installation process, consider performing an initial RAM disk driver update — refer to Section 13.2.3, “Preparing an initial RAM disk update”.
Devices with an equivalent device available
Because all devices of the same type are initialized together, you cannot update drivers for a device if the installation program has loaded drivers for a similar device. For example, consider a system that has two different network adapters, one of which has a driver update available. The installation program will initialize both adapters at the same time, and therefore, you will not be able to use this driver update. Again, complete the installation with the drivers loaded by the installation program and update to the new drivers after installation, or use an initial RAM disk driver update.

13.2. Preparing for a driver update during installation

If a driver update is necessary and available for your hardware, Red Hat or a trusted third party such as the hardware vendor will provide it in the form of an image file in ISO format. Some methods of performing a driver update require you to make the image file available to the installation program, others require you to use the image file to make a driver update disk, and one requires you to prepare an initial RAM disk update:
Methods that use the image file itself
  • local hard drive (IDE only)
  • USB storage device (for example, USB flash drive)
  • network (HTTP, FTP, NFS)
Methods that use a driver update disk produced from an image file
  • floppy disk
  • CD (IDE only)
  • DVD (IDE only)
  • USB storage device (for example, USB flash drive)
Methods that use an initial RAM disk update
  • PXE
Choose a method to provide the driver update, and refer to Section 13.2.1, “Preparing to use a driver update image file”, Section 13.2.2, “Preparing a driver update disk” or Section 13.2.3, “Preparing an initial RAM disk update”. Note that you can use a USB storage device either to provide an image file, or as a driver update disk.

Important

During installation, you cannot provide driver updates on media that is read by a device with a SATA or SCSI connection. For example, if the only optical drive on your system is a DVD drive with a SATA connection, you cannot provide a driver update on CD or DVD.

13.2.1. Preparing to use a driver update image file

13.2.1.1. Preparing to use an image file on local storage

To make the ISO image file available on local storage, such as a USB flash drive, USB hard drive, or local IDE hard drive, simply copy the file onto the storage device. You can rename the file if you find it helpful to do so, but you must not change the filename extension, which must remain .iso. In the following example, the file is named dd.iso:
Content of a USB flash drive holding a driver update image file

Figure 13.1. Content of a USB flash drive holding a driver update image file

Note that if you use this method, the storage device will contain only a single file. This differs from driver update disks on formats such as CD and DVD, which contain many files. The ISO image file contains all of the files that would normally be on a driver update disk.
If you change the file system label of the device to OEMDRV, the installation program will automatically examine it for driver updates and load any that it detects. This behavior is controlled by the dlabel=on boot option, which is enabled by default. Refer to Section 13.3.1, “Let the installer automatically find a driver update disk”.

13.2.1.2. Preparing to use an image file available through a network

To make the ISO image file available on a local network, place it in a publicly accessible folder on a HTTP, FTP, or NFS server. If you plan to use an image file that is already publicly available through the Internet, no special preparation is necessary. In either case, take note of the URL and verify that you can access the file from another machine on your network before commencing installation.

13.2.2. Preparing a driver update disk

You can use a variety of media to create a driver update disk, including CD, DVD, floppy disk, and USB storage devices such as USB flash drives

13.2.2.1. Creating a driver update disk on CD or DVD

Important

CD/DVD Creator is part of the GNOME desktop. If you use a different Linux desktop, or a different operating system altogether, you will need to use another piece of software to create the CD or DVD. The steps will be generally similar.
Make sure that the software that you choose can create CDs or DVDs from image files. While this is true of most CD and DVD burning software, exceptions exist. Look for a button or menu entry labeled burn from image or similar. If your software lacks this feature, or you do not select it, the resulting disk will hold only the image file itself, instead of the contents of the image file.
  1. Use the desktop file manager to locate the driver update ISO image file supplied to you by Red Hat or your hardware vendor.
    A typical .iso file displayed in a file manager window

    Figure 13.2. A typical .iso file displayed in a file manager window

  2. Right-click on this file and choose Write to disc. You will see a window similar to the following:
    CD/DVD Creator's Write to Disc dialog

    Figure 13.3. CD/DVD Creator's Write to Disc dialog

  3. Click the Write button. If a blank disc is not already in the drive, CD/DVD Creator will prompt you to insert one.
After you burn a driver update disk CD or DVD, verify that the disk was created successfully by inserting it into your system and browsing to it using the file manager. You should see a list of files similar to the following:
Contents of a typical driver update disc on CD or DVD

Figure 13.4. Contents of a typical driver update disc on CD or DVD

If you see only a single file ending in .iso, then you have not created the disk correctly and should try again. Ensure that you choose an option similar to burn from image if you use a Linux desktop other than GNOME or if you use a different operating system.

13.2.2.2. Creating a driver update disk on floppy disk, or USB storage device

Important

The following procedure assumes that you are creating a driver update disk using Linux. To create a driver update disk using a different operating system, you will need to find a tool that can extract files from ISO images. You must then place the extracted files on a removable disk or USB storage device.

Warning

If you perform this procedure with a disk or USB storage device that already contains data, this data will be destroyed with no warning. Make sure that you specify the correct disk or USB storage device, and make sure that this disk or storage device does not contain any data that you want to keep.
  1. Insert a blank, formatted floppy disk into an available drive, or connect an empty USB storage device (such as a USB flash drive) to your computer. Note the device name allocated to this disk, for example, /dev/fd0 for a floppy disk in the first floppy drive on your system.
    If you do not know the device name, become root and use the command fdisk -l on the command line. You will see a list of all storage devices available on your system. Compare the output of fdisk -l when the disk inserted or the storage device is attached with the output of this command when the disk is removed or the storage device is disconnected.
  2. At the command line, change into the directory that contains the image file.
  3. At the command line, type:
    dd if=image of=device
    where image is the image file, and device is the device name. For example, to create a driver disk on floppy disk /dev/fd0 from driver update image file dd.iso, you would use:
    dd if=dd.iso of=/dev/fd0
After you create a driver update disk, insert it (if you used a disk) or attach it (if you used a USB storage device) and browse to it using the file manager. If you see a list of files similar to those illustrated in Figure 13.4, “Contents of a typical driver update disc on CD or DVD”, you know that you have created the driver update disk correctly.

13.2.3. Preparing an initial RAM disk update

Important

This is an advanced procedure that you should consider only if you cannot perform a driver update with any other method.
The Red Hat Enterprise Linux installation program can load updates for itself early in the installation process from a RAM disk — an area of your computer's memory that temporarily behaves as if it were a disk. You can use this same capability to load driver updates. To perform a driver update during installation, your computer must be able to boot from a preboot execution environment (PXE) server, and you must have a PXE server available on your network. Refer to Chapter 34, PXE Network Installations for instructions on using PXE during installation.
To make the driver update available on your PXE server:
  1. Place the driver update image file on your PXE server. Usually, you would do this by downloading it to the PXE server from a location on the Internet specified by Red Hat or your hardware vendor. Names of driver update image files end in .iso.
  2. Copy the driver update image file into the /tmp/initrd_update directory.
  3. Rename the driver update image file to dd.img.
  4. At the command line, change into the /tmp/initrd_update directory, type the following command, and press Enter:
    find . | cpio --quiet -c -o | gzip -9 >/tmp/initrd_update.img
    
  5. Copy the file /tmp/initrd_update.img into the directory the holds the target that you want to use for installation. This directory is placed under the /tftpboot/pxelinux/ directory. For example, /tftpboot/pxelinux/r5su3/ might hold the PXE target for Red Hat Enterprise Linux 5.3 Server.
  6. Edit the /tftpboot/pxelinux/pxelinux.cfg/default file to include an entry that includes the initial RAM disk update that you just created, in the following format:
    label target-dd
    kernel target/vmlinuz
    append initrd=target/initrd.img,target/dd.img
    
    Where target is the target that you want to use for installation.

Example 13.1. Preparing an initial RAM disk update from a driver update image file

In this example, driver_update.iso is a driver update image file that you downloaded from the Internet to a directory on your PXE server. The target that you want to PXE boot from is located in /tftpboot/pxelinux/r5su3
At the command line, change to the directory that holds the file and enter the following commands:
$ cp driver_update.iso /tmp/initrd_update/dd.img
$ cd /tmp/initrd_update
$ find . | cpio --quiet -c -o | gzip -9 >/tmp/initrd_update.img
$ cp /tmp/initrd_update.img /tftpboot/pxelinux/r5su3/dd.img
Edit the /tftpboot/pxelinux/pxelinux.cfg/default file and include the following entry:
label r5su3-dd
kernel r5su3/vmlinuz
append initrd=r5su3/initrd.img,r5su3/dd.img
Refer to Section 13.3.5, “Select a PXE target that includes a driver update” to learn how to use an initial RAM disk update during installation.

13.3. Performing a driver update during installation

You can perform a driver update during installation in the following ways:
  • let the installer automatically find a driver update disk.
  • let the installer prompt you for a driver update.
  • use a boot option to specify a driver update disk.
  • use a boot option to specify a driver update image file on a network.
  • select a PXE target that includes a driver update.

13.3.1. Let the installer automatically find a driver update disk

Attach a block device with the filesystem label OEMDRV before starting the installation process. The installer will automatically examine the device and load any driver updates that it detects and will not prompt you during the process. Refer to Section 13.2.1.1, “Preparing to use an image file on local storage” to prepare a storage device for the installer to find.

13.3.2. Let the installer prompt you for a driver update

  1. Begin the installation normally for whatever method you have chosen. If the installer cannot load drivers for a piece of hardware that is essential for the installation process (for example, if it cannot detect any network or storage controllers), it prompts you to insert a driver update disk:
    The no driver found dialog

    Figure 13.5. The no driver found dialog

13.3.3. Use a boot option to specify a driver update disk

Important

This method only works to introduce completely new drivers, not to update existing drivers.
  1. Type linux dd at the boot prompt at the start of the installation process and press Enter. The installer prompts you to confirm that you have a driver disk:
    The driver disk prompt

    Figure 13.6. The driver disk prompt

  2. Insert the driver update disk that you created on CD, DVD, floppy disk, or USB storage device and select Yes. The installer examines the storage devices that it can detect. If there is only one possible location that could hold a driver disk (for example, the installer detects the presence of a floppy disk, but no other storage devices) it will automatically load any driver updates that it finds at this location.
    If the installer finds more than one location that could hold a driver update, it prompts you to specify the location of the update. Refer to to Section 13.4, “Specifying the location of a driver update image file or driver update disk” .

13.3.4. Use a boot option to specify a driver update image file on a network

Important

This method only works to introduce completely new drivers, not to update existing drivers.
Type linux dd=URL (where URL is the HTTP, FTP, or NFS address of a driver update image) at the boot prompt at the start of the installation process and press Enter. The installer will retrieve the driver update image from that address and use it during installation.

13.3.5. Select a PXE target that includes a driver update

  1. Select network boot in your computer's BIOS or boot menu. The procedure to specify this option varies widely among different computers. Consult your hardware documentation or the hardware vendor for specifics relevant to your computer.
  2. In the preexecution boot environment (PXE), choose the boot target that you prepared on your PXE server. For example, if you labeled this environment r5su3-dd in the /tftpboot/pxelinux/pxelinux.cfg/default file on your PXE server, type r5su3-dd at the prompt and press Enter.
Refer to Section 13.2.3, “Preparing an initial RAM disk update” and Chapter 34, PXE Network Installations for instructions on using PXE to perform an update during installation. Note that this is an advanced procedure — do not attempt it unless other methods of performing a driver update fail.

13.4. Specifying the location of a driver update image file or driver update disk

If the installer detects more than one possible device that could hold a driver update, it prompts you to select the correct device. If you are not sure which option represents the device on which the driver update is stored, try the various options in order until you find the correct one.
Selecting a driver disk source

Figure 13.7. Selecting a driver disk source

If the device that you choose contains no suitable update media, the installer will prompt you to make another choice.
If you made a driver update disk on floppy disk, CD, DVD, or USB storage device, the installer now loads the driver update. However, if the device that you selected is a type of device that could contain more than one partition (whether the device currently has more than one partition or not), the installer might prompt you to select the partition that holds the driver update.
Selecting a driver disk partition

Figure 13.8. Selecting a driver disk partition

The installer prompts you to specify which file contains the driver update:
Selecting an ISO image

Figure 13.9. Selecting an ISO image

Expect to see these screens if you stored the driver update on an internal hard drive or on a USB storage device. You should not see them if the driver update is on a floppy disk, CD, or DVD.
Regardless of whether you are providing a driver update in the form of an image file or with a driver update disk, the installer now copies the appropriate update files into a temporary storage area (located in system RAM and not on disk). The installer might ask whether you would like to use additional driver updates. If you select Yes, you can load additional updates in turn. When you have no further driver updates to load, select No. If you stored the driver update on removeable media, you can now safely eject or disconnect the disk or device. The installer no longer requires the driver update, and you can re-use the media for other purposes.

Chapter 14. Troubleshooting Installation on an IBM POWER System

This appendix discusses some common installation problems and their solutions.
You may also find the IBM Online Alert Section for System p and System i useful. It is located at:
http://www14.software.ibm.com/webapp/set2/sas/f/lopdiags/info/LinuxAlerts.html
Please note that the url above has been split across two lines for readability. It should be entered into a browser as one continuous line, with no linebreak.

14.1. You are Unable to Boot Red Hat Enterprise Linux

14.1.1. Is Your System Displaying Signal 11 Errors?

A signal 11 error, commonly know as a segmentation fault, means that the program accessed a memory location that was not assigned to it. A signal 11 error may be due to a bug in one of the software programs that is installed, or faulty hardware.
If you receive a fatal signal 11 error during your installation, it is probably due to a hardware error in memory on your system's bus. Like other operating systems, Red Hat Enterprise Linux places its own demands on your system's hardware. Some of this hardware may not be able to meet those demands, even if they work properly under another OS.
Ensure that you have the latest installation updates and images from Red Hat. Review the online errata to see if newer versions are available. If the latest images still fail, it may be due to a problem with your hardware. Commonly, these errors are in your memory or CPU-cache. A possible solution for this error is turning off the CPU-cache in the BIOS, if your system supports this. You could also try to swap your memory around in the motherboard slots to check if the problem is either slot or memory related.
Another option is to perform a media check on your installation CD-ROMs. The Red Hat Enterprise Linux installation program has the ability to test the integrity of the installation media. It works with the CD, DVD, hard drive ISO, and NFS ISO installation methods. Red Hat recommends that you test all installation media before starting the installation process, and before reporting any installation-related bugs (many of the bugs reported are actually due to improperly-burned CDs). To use this test, type the following command at the boot: or yaboot: prompt (prepend with elilo for Itanium systems):
	linux mediacheck
For more information concerning signal 11 errors, refer to:
	http://www.bitwizard.nl/sig11/

14.2. Trouble Beginning the Installation

14.2.1. Problems with Booting into the Graphical Installation

There are some video cards that have trouble booting into the graphical installation program. If the installation program does not run using its default settings, it tries to run in a lower resolution mode. If that still fails, the installation program attempts to run in text mode.
One possible solution is to try using the resolution= boot option. Refer to Chapter 15, Additional Boot Options for IBM Power Systems for more information.

Note

To disable frame buffer support and allow the installation program to run in text mode, try using the nofb boot option. This command may be necessary for accessibility with some screen reading hardware.

14.3. Trouble During the Installation

14.3.1. No devices found to install Red Hat Enterprise Linux Error Message

If you receive an error message stating No devices found to install Red Hat Enterprise Linux, there is probably a SCSI controller that is not being recognized by the installation program.
Check your hardware vendor's website to determine if a driver diskette image is available that fixes your problem. For more general information on driver diskettes, refer to Chapter 13, Updating drivers during installation on IBM POWER systems.
You can also refer to the Red Hat Hardware Compatibility List, available online at:

14.3.2. Saving Traceback Messages Without a Diskette Drive

If you receive a traceback error message during installation, you can usually save it to a diskette.
If you do not have a diskette drive available in your system, you can scp the error message to a remote system.
This information does not apply to users of headless IBM System p systems.
When the traceback dialog appears, the traceback error message is automatically written to a file named /tmp/anacdump.txt. Once the dialog appears, switch over to a new tty (virtual console) by pressing the keys Ctrl+Alt+F2 and scp the message written to /tmp/anacdump.txt to a known working remote system.

14.3.3. Trouble with Partition Tables

If you receive an error after the Disk Partitioning Setup (Section 12.16, “Disk Partitioning Setup”) phase of the installation saying something similar to
The partition table on device hda was unreadable. To create new partitions it must be initialized, causing the loss of ALL DATA on this drive.
you may not have a partition table on that drive or the partition table on the drive may not be recognizable by the partitioning software used in the installation program.
No matter what type of installation you are performing, backups of the existing data on your systems should always be made.

14.3.4.  Other Partitioning Problems for IBM™ POWER System Users

If you are using Disk Druid to create partitions, but cannot move to the next screen, you probably have not created all the partitions necessary for Disk Druid's dependencies to be satisfied.
You must have the following partitions as a bare minimum:
  • A / (root) partition
  • A <swap> partition of type swap
  • A PPC PReP Boot partition.
  • A /boot/ partition.

Note

When defining a partition's type as swap, do not assign it a mount point. Disk Druid automatically assigns the mount point for you.

14.3.5. Are You Seeing Python Errors?

During some upgrades or installations of Red Hat Enterprise Linux, the installation program (also known as anaconda) may fail with a Python or traceback error. This error may occur after the selection of individual packages or while trying to save the upgrade log in the /tmp/directory. The error may look similar to:
Traceback (innermost last):
File "/var/tmp/anaconda-7.1//usr/lib/anaconda/iw/progress_gui.py", line 20, in run
rc = self.todo.doInstall ()    
File "/var/tmp/anaconda-7.1//usr/lib/anaconda/todo.py", line 1468, in doInstall 
self.fstab.savePartitions ()    
File "fstab.py", line 221, in savePartitions      
sys.exit(0)  
SystemExit: 0   
Local variables in innermost frame:  
self: <fstab.GuiFstab instance at 8446fe0>  
sys: <module 'sys' (built-in)>  
ToDo object:  (itodo  ToDo  p1  (dp2  S'method'  p3  (iimage  CdromInstallMethod  
p4  (dp5  S'progressWindow'  p6   <failed>
This error occurs in some systems where links to /tmp/ are symbolic to other locations or have been changed since creation. These symbolic or changed links are invalid during the installation process, so the installation program cannot write information and fails.
If you experience such an error, first try to download any available errata for anaconda. Errata can be found at:
http://www.redhat.com/support/errata/
The anaconda website may also be a useful reference and can be found online at:
http://fedoraproject.org/wiki/Anaconda
You can also search for bug reports related to this problem. To search Red Hat's bug tracking system, go to:
http://bugzilla.redhat.com/bugzilla/
Finally, if you are still facing problems related to this error, register your product and contact our support team. To register your product, go to:
http://www.redhat.com/apps/activate/

14.4. Problems After Installation

14.4.1. Unable to IPL from *NWSSTG

If you are experiencing difficulties when trying to IPL from *NWSSTG, you may not have created a PReP Boot partition set as active.

14.4.2. Booting into a Graphical Environment

If you have installed the X Window System but are not seeing a graphical desktop environment once you log into your Red Hat Enterprise Linux system, you can start the X Window System graphical interface using the command startx.
Once you enter this command and press Enter, the graphical desktop environment is displayed.
Note, however, that this is just a one-time fix and does not change the log in process for future log ins.
To set up your system so that you can log in at a graphical login screen, you must edit one file, /etc/inittab, by changing just one number in the runlevel section. When you are finished, reboot the computer. The next time you log in, you are presented with a graphical login prompt.
Open a shell prompt. If you are in your user account, become root by typing the su command.
Now, type gedit /etc/inittab to edit the file with gedit. The file /etc/inittab opens. Within the first screen, a section of the file which looks like the following appears:
# Default runlevel. The runlevels used by RHS are: 
#   0 - halt (Do NOT set initdefault to this) 
#   1 - Single user mode 
#   2 - Multiuser, without NFS (The same as 3, if you do not have networking) 
#   3 - Full multiuser mode 
#   4 - unused 
#   5 - X11 
#   6 - reboot (Do NOT set initdefault to this) 
#  id:3:initdefault:
To change from a console to a graphical login, you should change the number in the line id:3:initdefault: from a 3 to a 5.

Warning

Change only the number of the default runlevel from 3 to 5.
Your changed line should look like the following:
	 id:5:initdefault: 
When you are satisfied with your change, save and exit the file using the Ctrl+Q keys. A window appears and asks if you would like to save the changes. Click Save.
The next time you log in after rebooting your system, you are presented with a graphical login prompt.

14.4.3. Problems with the X Window System (GUI)

If you are having trouble getting X (the X Window System) to start, you may not have installed it during your installation.
If you want X, you can either install the packages from the Red Hat Enterprise Linux CD-ROMs or perform an upgrade.
If you elect to upgrade, select the X Window System packages, and choose GNOME, KDE, or both, during the upgrade package selection process.

14.4.4. Problems with the X Server Crashing and Non-Root Users

If you are having trouble with the X server crashing when anyone other than root logs in, you may have a full file system (or, a lack of available hard drive space).
To verify that this is the problem you are experiencing, run the following command:
df -h
The df command should help you diagnose which partition is full. For additional information about df and an explanation of the options available (such as the -h option used in this example), refer to the df man page by typing man df at a shell prompt.
A key indicator is 100% full or a percentage above 90% or 95% on a partition. The /home/ and /tmp/ partitions can sometimes fill up quickly with user files. You can make some room on that partition by removing old files. After you free up some disk space, try running X as the user that was unsuccessful before.

14.4.5. Problems When You Try to Log In

If you did not create a user account in the Setup Agent, log in as root and use the password you assigned to root.
If you cannot remember your root password, boot your system as linux single.
Once you have booted into single user mode and have access to the # prompt, you must type passwd root, which allows you to enter a new password for root. At this point you can type shutdown -r now to reboot the system with the new root password.
If you cannot remember your user account password, you must become root. To become root, type su - and enter your root password when prompted. Then, type passwd <username>. This allows you to enter a new password for the specified user account.
If the graphical login screen does not appear, check your hardware for compatibility issues. The Hardware Compatibility List can be found at:
	http://hardware.redhat.com/hcl/

14.4.6. Your Printer Does Not Work

If you are not sure how to set up your printer or are having trouble getting it to work properly, try using the Printer Configuration Tool.
Type the system-config-printer command at a shell prompt to launch the Printer Configuration Tool. If you are not root, it prompts you for the root password to continue.

14.4.7. Apache-based httpd service/Sendmail Hangs During Startup

If you are having trouble with the Apache-based httpd service or Sendmail hanging at startup, make sure the following line is in the /etc/hosts file:
127.0.0.1  localhost.localdomain  localhost

Chapter 15. Additional Boot Options for IBM Power Systems

This section discusses additional boot and kernel boot options available for the Red Hat Enterprise Linux installation program.
To use any of the boot options presented here, type the command you wish to invoke at the installation boot: prompt.

Boot Time Command Arguments

askmethod
this command asks you to select the installation method you would like to use when booting from the Red Hat Enterprise Linux CD-ROM.
dd
this argument causes the installation program to prompt you to use a driver diskette.
dd=url
this argument causes the installation program to prompt you to use a driver image from a specified HTTP, FTP, or NFS network address.
display=ip:0
this command allows remote display forwarding. In this command, ip should be replaced with the IP address of the system on which you want the display to appear.
On the system you want the display to appear on, you must execute the command xhost +remotehostname, where remotehostname is the name of the host from which you are running the original display. Using the command xhost +remotehostname limits access to the remote display terminal and does not allow access from anyone or any system not specifically authorized for remote access.
driverdisk
this command performs the same function as the dd command and also prompts you to use a driver diskette during the installation of Red Hat Enterprise Linux.
ide=nodma
this command disables DMA on all IDE devices and may be useful when having IDE-related problems.
mediacheck
this command gives you the option of testing the integrity of the install source (if an ISO-based method). this command works with the CD, DVD, hard drive ISO, and NFS ISO installation methods. Verifying that the ISO images are intact before you attempt an installation helps to avoid problems that are often encountered during an installation.
mem=xxxm
this command allows you to override the amount of memory the kernel detects for the machine. This may be needed for some older systems where only 16 mb is detected and for some new machines where the video card shares the video memory with the main memory. When executing this command, xxx should be replaced with the amount of memory in megabytes.
mpath
enables multipath support.

Important

If you install Red Hat Enterprise Linux 5.11 on a network storage device accessible through multiple paths, you must boot the installation process with this option. If you do not specify this option at boot time, installation will fail, or the system will fail to boot after installation completes.
noeject
do not eject optical discs after installation. This option is useful in remote installations where it is difficult to close the tray afterwards.
nopass
this command disables the passing of keyboard and mouse information to stage 2 of the installation program. It can be used to test keyboard and mouse configuration screens during stage 2 of the installation program when performing a network installation.
nopcmcia
this command ignores any PCMCIA controllers in system.
noprobe
this command disables hardware detection and instead prompts the user for hardware information.
noshell
this command disables shell access on virtual console 2 during an installation.
nostorage
this command disables probing for SCSI and RAID storage hardware.
nousb
this command disables the loading of USB support during the installation. If the installation program tends to hang early in the process, this command may be helpful.
nousbstorage
this command disables the loading of the usbstorage module in the installation program's loader. It may help with device ordering on SCSI systems.
rescue
this command runs rescue mode. Refer to Chapter 27, Basic System Recovery for more information about rescue mode.
resolution=
tells the installation program which video mode to run. it accepts any standard resolution, such as 640x480, 800x600, 1024x768, and so on.
serial
this command turns on serial console support.
text
this command disables the graphical installation program and forces the installation program to run in text mode.
updates
this command prompts you to insert a floppy diskette containing updates (bug fixes) for the anaconda installation program. It is not needed if you are performing a network installation and have already placed the updates image contents in rhupdates/ on the server.
vnc
this command allows you to install from a VNC server.
vncpassword=
this command sets the password used to connect to the VNC server.

Part III. IBM System z Architecture - Installation and Booting

The Red Hat Enterprise Linux Installation Guide for IBM System z Architecture systems discusses the installation of Red Hat Enterprise Linux and some basic post-installation troubleshooting. Advanced installation options are covered in the second part of this manual.

Chapter 16. Steps to Get You Started

16.1. Pre-Installation

The installation process assumes a basic familiarity with the IBM eServer System z platforms. For additional information on these platforms, refer to the IBM Redbooks available online at:
http://www.redbooks.ibm.com/
This manual assumes you are familiar with the related Redbooks and can set up logical partitions (LPARs) and virtual machines (VMs) on an IBM eServer System z system.

Note

For the most current IBM resources, visit http://www.ibm.com/eserver/zseries/.
Before you install Red Hat Enterprise Linux, you must perform the following steps:
  1. Allocate sufficient Disk Storage Space using DASDs [8] or SCSI[9] partitions to provide suitable disk space (for example, 2 GB is sufficient for server installations, while 5 GB is minimally required to install all packages).

    Important

    Red Hat Enterprise Linux 5 cannot use unformatted DASDs when installing with kickstart and the cmdline user interface. Refer to the clearpart documentation in Section 31.4, “Kickstart Options” for a method to ensure that DASDs are formatted during installation.
  2. Acquire a minimum of 512 MB RAM (1 GB is strongly recommended) to designate for the Linux virtual machine.
  3. Determine if you need swap space and if so how much. While it is possible (and recommended) to assign enough memory to z/VM and let z/VM do the necessary swapping, there may be cases where the amount of required RAM is not predictable. Such instances should be examined on a case-by-case basis.
  4. Decide on the environment under which to run the operating system (on an LPAR or as a guest operating system on one or more virtual machines).
  5. Finally, it is important to review sections 3.3 through 3.8, and Chapters 5 and 6 of the IBM Linux for System z Redbook, as it explains the different configurations and install scenarios available on the zSeries platform as well as how to setup an initial LPAR or Linux virtual machine (z/VM).

16.2. Additional Hardware Preparation for System z

The network configuration must be determined beforehand. Red Hat Enterprise Linux for IBM System z supports QDIO-enabled (Queued Direct I/O) and LCS (LAN channel station) devices. The CTC (channel-to-channel) and IUCV (inter-user communication vehicle) are deprecated and are not supported in Red Hat Enterprise Linux.
For the purposes of this installation, it is recommended that at least 4 GB of disk space (such as two 2 GB DASD, direct access storage device, partitions or equivalent IBM System z SCSI LUNs) be allocated for the installation process. All DASD disk allocations should be completed prior to the installation process. After the installation, more DASD or SCSI (for IBM System z only) disk partitions may be added or deleted as necessary.

16.3. Basic Overview of the Boot Method

To prepare for installation, you must have the Linux kernel (kernel.img), the ram disk (initrd.img), and if using z/VM, an optional CMS configuration file (redhat.conf) and a parameter file. Sample parameter and CMS configuration files are provided (redhat.parm and redhat.conf). You should edit the CMS configuration file and add information about your DASD. You may also want to add some information about your network configuration. Once this is started on the IBM System z, the networking is configured. You can then use ssh on another computer to log into your installation image. Now you can start an installation script to install Red Hat Enterprise Linux.

16.4. Preparing for a Network Installation

Ensure that you have boot media available on CD, DVD, or a USB storage device such as a flash drive.
The Red Hat Enterprise Linux installation media must be available for either a network installation (via NFS, FTP, or HTTP) or installation via local storage. Use the following steps if you are performing an NFS, FTP, or HTTP installation.
The NFS, FTP, or HTTP server to be used for installation over the network must be a separate machine which can provide the complete contents of the installation DVD-ROM or the installation CD-ROMs.

Note

In the following examples, the directory on the installation staging server that will contain the installation files will be specified as /location/of/disk/space. The directory that will be made publicly available via FTP, NFS, or HTTP will be specified as /publicly/available/directory. For example, /location/of/disk/space may be a directory you create called /var/isos. /publicly/available/directory might be /var/www/html/rhel5, for an HTTP install.
To copy the files from the installation DVD or CD-ROMs to a Linux machine which acts as an installation staging server, perform the following steps:
  • Create an iso image from the installation disk(s) using the following command (for DVDs):
    dd if=/dev/dvd of=/location/of/disk/space/RHEL5.iso
    where dvd refers to your DVD drive device.

16.4.1. Preparing for FTP and HTTP installation

If you are setting up an installation tree for NFS, FTP, or HTTP installations, you must copy the RELEASE-NOTES files and all files from the RedHat directory on all operating systems ISO images. On Linux and UNIX systems, the following process will properly configure the target directory on your server (repeat for each CD-ROM/ISO image):
  1. Insert CD-ROM or DVD-ROM.
  2. mount /media/cdrom
  3. If you are installing the Server variant, run cp -a /media/cdrom/Server <target-directory>
    If you are installing the Client variant, run cp -a /media/cdrom/Client <target-directory>
  4. cp /media/cdrom/RELEASE-NOTES* <target-directory> (Installation CD 1 or DVD only)
  5. cp /media/cdrom/images <target-directory> (Installation CD 1 or DVD only)
  6. umount /media/cdrom
(Where <target-directory> represents the path to the directory to contain the installation tree.)

Note

Do not copy the Supplementary ISO image, or any of the layered product ISO images, as this will overwrite files necessary for Anaconda's proper operation.
These ISO images must be installed after Red Hat Enterprise Linux has been installed.
Next make sure that the /publicly/available/directory directory is shared via FTP or HTTP, and verify client access. You can check to see whether the directory is accessible from the server itself, and then from another machine on the same subnet that you will be installing to.

16.4.2. Preparing for an NFS install

For NFS installation it is not necessary to mount the iso image. It is sufficient to make the iso image itself available via NFS. You can do this by moving the iso image or images to the NFS exported directory:
  • For DVD:
    mv /location/of/disk/space/RHEL5.iso /publicly/available/directory/
  • For CDROMs:
    mv /location/of/disk/space/disk*.iso /publicly/available/directory/
Ensure that the /publicly/available/directory directory is exported via NFS via an entry in /etc/exports.
To export to a specific system:
/publicly/available/directory client.ip.address
To export to all systems use an entry such as:
/publicly/available/directory *
Start the NFS daemon (on a Red Hat Enterprise Linux system, use /sbin/service nfs start). If NFS is already running, reload the configuration file (on a Red Hat Enterprise Linux system use /sbin/service nfs reload).
Be sure to test the NFS share following the directions in the Red Hat Enterprise Linux Deployment Guide.

16.5. Preparing for a Hard Drive Installation

Note

Hard drive installations using DASD or SCSI source storage only work from native ext2 or ext3 partitions. If you have a file system based on devices other than native ext2 or ext3 (particularly a file system based on RAID or LVM partitions) you will not be able to use it as a source to perform a hard drive installation.
Ensure that you have boot media available on CD, DVD, or a USB storage device such as a flash drive.
To prepare your system for a hard drive installation, you must set the system up in one of the following ways:
  • Using a set of CD-ROMs, or a DVD — Create ISO image files from each installation CD-ROM, or from the DVD. For each CD-ROM (once for the DVD), execute the following command on a Linux system:
    dd if=/dev/cdrom of=/tmp/file-name.iso
    This command may raise an error message when the data at the end of the CD-ROM is reached which can be ignored. The ISO images created can now be used for installation, once copied to the correct DASD.
  • Using ISO images - transfer these to the system to be installed (or to the correct DASD or SCSI devices).
    Verifying that ISO images are intact before you attempt an installation, helps to avoid problems. To verify the ISO images are intact prior to performing an installation, use an md5sum program (many md5sum programs are available for various operating systems). An md5sum program should be available on the same Linux machine as the ISO images.
    Make the correct DASDs or SCSI LUNs accessible to the new VM or LPAR, and then proceed with installation.
    Additionally, if a file called updates.img exists in the location from which you install, it is used for updates to anaconda, the installation program. Refer to the file install-methods.txt in the anaconda RPM package for detailed information on the various ways to install Red Hat Enterprise Linux, as well as how to apply the installation program updates.

16.6. Installing under z/VM

Log onto z/VM as the Linux guest account. You can use x3270 or c3270 (from the x3270-text package in Red Hat Enterprise Linux) to log in to z/VM from other Linux systems. Alternatively, use the 3270 terminal emulator on the IBM System z management console. If you are working from a Windows based machine, Jolly Giant (http://www.jollygiant.com) offers an SSL-enabled 3270 emulator.
If you are not in CMS mode, enter it now.
i cms
If necessary, add the device containing z/VM's TCP/IP tools to your CMS disk list. For example:
vmlink tcpmaint 592 592
If using any of the qdio/qeth based network connection types (such as OSA express or hipersockets), set the VM guest qioassist parameter off:
set qioassist off
FTP to the machine containing the boot images (kernel.img and initrd.img), log in, and execute the following commands. Use the (repl option if you are overwriting existing kernel.img, initrd.img, generic.prm, or redhat.exec files:
cd /location/of/boot/images//images/ 
locsite fix 80  
bin 
get kernel.img (repl  
get initrd.img (repl  
ascii  
get generic.prm (repl  
get redhat.exec (repl  
quit
You may now create the parameter file (for example, redhat.parm). Refer to Chapter 19, Sample Parameter Files for sample parm files. Below is an explanation of the parm file contents.
There is a limit of 32 total parameters in the parameter file. In order to accommodate limitations with parameter files, a new configuration file on a CMS DASD should be used to configure the initial network setup and the DASD specification.
A .parm file is still required for the real kernel parameters, such as root=/dev/ram0 ro ip=off ramdisk_size=40000, and single parameters which are not assigned to variables, such as vnc. Two parameters which are used in z/VM installs to point the installation program at the new CMS configuration file need to be added to the .parm file:
CMSDASD=191 CMSCONFFILE=redhat.conf
CMSDASD is the device ID of the CMS formatted DASD which contains the configuration file. CMSDASD is often the 'A' DASD (usually disk 191) of the z/VM guest account. The name of the configuration file must be set with CMSCONFFILE and needs to be all lowercase.
The syntax of the CMSCONFFILE is bash style with variable="value" pairs, one on each line.
Example redhat.parm file:
root=/dev/ram0 ro ip=off ramdisk_size=40000
CMSDASD=191 CMSCONFFILE=redhat.conf
vnc
The content of the redhat.exec file shipped by Red Hat is:
/* */                    
'cl rdr'                 
'purge rdr all'          
'spool punch * rdr'      
'PUNCH KERNEL IMG A (NOH'
'PUNCH REDHAT PARM A (NOH'
'PUNCH INITRD IMG A (NOH'
'ch rdr all keep nohold' 
'i 00c'
Example redhat.conf file:
HOSTNAME="foobar.systemz.example.com"
DASD="200-203"
NETTYPE="qeth"
IPADDR="192.168.17.115"
SUBCHANNELS="0.0.0600,0.0.0601,0.0.0602"
PORTNAME="FOOBAR"
NETWORK="192.168.17.0"
NETMASK="255.255.255.0"
BROADCAST="192.168.17.255"
SEARCHDNS="example.com:systemz.example.com"
GATEWAY="192.168.17.254"
DNS="192.168.17.1"
MTU="4096"
The following parameters are required and must be included in the parameter file:
  • DASD=dasd-list
    Where dasd-list represents the list of DASD devices to be used by Red Hat Enterprise Linux.
    Although autoprobing for DASDs is done if this parameter is omitted, it is highly recommended to include the DASD= parameter, as the device numbers (and therefore the device names) can vary when a new DASD is added to the Red Hat Enterprise Linux guest. This can result in an unusable system.
    Additionally, in SAN-based environments, autoprobing in an LPAR-based install may have unintended side effects, as the number of DASD and SCSI volumes visible may be unexpectedly large and include volumes currently in use by other users. In particular, autoprobing during a kickstart install (which may have enabled autopartitioning to clear all partitions) is highly discouraged.
  • root=file-system
    where file-system represents the device on which the root file system can be found. For installation purposes, it should be set to /dev/ram0, which is the ramdisk containing the Red Hat Enterprise Linux installation program.
The following parameters are required to set up networking:
  • SUBCHANNELS=
    Provides required device bus IDs for the various network interfaces.
    qeth: SUBCHANNELS="read_device_bus_id,write_device_bus_id, data_device_bus_id"
    lcs: SUBCHANNELS="read_device_bus_id,write_device_bus_id"
    For example (a sample qeth SUBCHANNEL statement):
    SUBCHANNELS=0.0.0600,0.0.0601,0.0.0602
The following parameters are optional:
  • HOSTNAME=string
    Where string is the hostname of the newly-installed Linux guest.
  • NETTYPE=type
    Where type must be one of the following: lcs, or qeth.
    Choose lcs for:
    • OSA-2 Ethernet/Token Ring
    • OSA-Express Fast Ethernet in non-QDIO mode
    • OSA-Express High Speed Token Ring in non-QDIO mode
    • Gigabit Ethernet in non-QDIO mode
    Choose qeth for:
    • OSA-Express Fast Ethernet
    • Gigabit Ethernet (including 1000Base-T)
    • High Speed Token Ring
    • HiperSockets
    • ATM (running Ethernet LAN emulation)
  • IPADDR=IP
    Where IP is the IP address of the new Linux guest.
  • NETWORK=network
    Where network is the address of your network.
  • NETMASK=netmask
    Where netmask is the netmask.
  • BROADCAST=broadcast
    Where broadcast is the broadcast address.
  • GATEWAY=gw
    Where gw is the gateway-IP for your eth device.
  • MTU=mtu
    Where mtu is the Maximum Transmission Unit (MTU) for this connection.
  • DNS=server1:server2::serverN
    Where server1:server2::serverN is a list of DNS servers, separated by colons. For example:
    DNS=10.0.0.1:10.0.0.2
  • SEARCHDNS=domain1:domain2::domainN
    Where domain1:domain2::domainN is a list of the search domains, separated by colons. For example:
    SEARCHDNS=example.com:example.org
  • PORTNAME=osa_portname | lcs_portnumber
    This variable supports OSA devices operating in qdio mode or non-qdio mode.
    When using qdio mode: osa_portname is the portname specified on the OSA device when operating in qeth mode. PORTNAME is only required for z/VM 4.3 or older without APARs VM63308 and PQ73878.
    When using non-qdio mode: lcs_portnumber is used to pass the relative port number as integer in the range of 0 through 15.
  • FCP_n="device_number SCSI_ID WWPN SCSI_LUN FCP_LUN"
    The variables can be used on systems with FCP devices to preconfigure the FCP setup and can be subsequently edited in anaconda during the installation. An example value may look similar to:
    FCP_1="0.0.5000 0x01 0x5105074308c212e9 0x0 4010"
    • n is an integer value (e.g. FCP_1, FCP_2, ...).
    • device_number is used to specify the address of the FCP device ( 0.0.5000 for device 5000, for example).
    • SCSI_ID is specified in hex-value, typically sequential values (e.g. 0x01, 0x02 ... ) are used over multiple FCP_ variables.
    • WWPN is the world wide port name used for routing (often in conjunction with multipathing) and is as a 16-digit hex value (e.g. 0x5105074308c212e9).
    • SCSI_LUN refers to the local SCSI logical unit value and is specified as a hex-value, typically sequential values (e.g. 0x00, 0x01, ...) are used over multiple FCP_ variables.
    • FCP_LUN refers to the storage logical unit identifier and is specified as a hex-value (such as 0x4010).

    Note

    Each of the values used in the FCP parameters (FCP_1, FCP_2, ...) are site-specific and are normally supplied by the FCP storage administrator.

Important

Anaconda now supports both ports on CHPID for OSA Express3 cards. The installer will prompt for the port number in the initial stage of the installation. The value provided for the port also affects installed network interface startup script. When port 1 is selected, the value "portno=1" is added to OPTIONS parameter of ifcfg-eth* file.
When installing under z/VM, you can add either PORTNO=0 (to use port 0) or PORTNO=1 (to use port 1) to the CMS configuration file to avoid being prompted for the mode.

Important

When installing on a System z guest for Red Hat Enterprise Linux 5.2, you can make the mode persistent by adding either LAYER2=0 or LAYER2=1 to the CMS configuration file. Use LAYER2=0 when the OSA is in layer 3 mode, and LAYER2=1 when the OSA is in layer 2 mode.
When specifying LAYER2=1, you can also specify VSWITCH=1 when connecting to a VSWITCH, or VSWITCH=0 when connecting directly to the OSA. If a VSWITCH is not in use, specify the MAC address in the CMS configuration file using the parameter MACADDR=<MAC address>.
The following parameters for kickstart installations are optional:
  • RUNKS=value
    Where value is defined as 1 if you want to run the installation program in noninteractive (kickstart) mode in the 3270 terminal, or 0 otherwise.
  • cmdline
    When cmdline is specified, 3270 terminal output becomes much more readable, as the installer disables most escape terminal sequences that are applicable to unix-like consoles, but not supported on the 3270 console.
  • Make sure that your kickstart file contains all required parameters before you use either of the RUNKS of cmdline options.
If any of the network parameters required to make the network operate correctly are omitted from the parm file, a prompt appears during the installation boot process.
If you logged off, reconnect and log in using z/VM guest ID you configured for installation. If you are not in CMS mode, enter it now.
i cms
Use the downloaded REXX script redhat.exec that contains the commands necessary to IPL the kernel image and start the installation. After having IPLed CMS, enter redhat on the 3270 console and press the Enter key to execute this script.
The initial installation start-up script prompts you for information about your networking and DASDs unless you have specified all necessary information in the parm file.
Once all questions have been answered, you are ready to begin the core installation program, loader. To continue with the installation, refer to Chapter 17, Installing on IBM System z Systems for further instructions.

16.7. Installing in an LPAR using the Red Hat Enterprise Linux LPAR CD

The following steps must be taken when installing onto an LPAR.
  • Log in on the Hardware Master Console (HMC) or the Support Element Workplace (SEW) as a user with sufficient privileges to install a new OS to an LPAR. The SYSPROG user is recommended.
  • Select Images, then select the LPAR to which you wish to install. Use the arrows in the frame on the right side to navigate to the CPC Recovery menu.
  • Double-click on Load from CD-ROM or Server.
  • In the dialog box that follows, select Local CD-ROM then click Continue.
  • In the dialog that follows, keep the default selection of generic.ins then click Continue.

16.8. Installing in an LPAR without the Red Hat Enterprise Linux for System z CD-ROMs

  • Log in on the Support Element Workplace as a user with sufficient privileges to install a new OS to an LPAR.
  • Select Images, then select the LPAR you wish to install to.
  • Use the arrows in the frame on the right side to navigate to the CPC Recovery menu.
  • Double-click on Load from CD-ROM or Server.
  • In the dialog box that follows, select FTP Source, and enter the following information:
    Host Computer:
    Hostname or IP address of the FTP server you wish to install from (for example, ftp.redhat.com)
    User ID:
    Your user name on the FTP server (or anonymous)
    Password:
    Your password (use your email address if you are logging in as anonymous)
    Account:
    Leave this field empty
    File location (can be left blank):
    Directory on the FTP server holding Red Hat Enterprise Linux for System z (for example, /pub/redhat/linux/rawhide/s390x)
  • Click Continue.
  • In the dialog that follows, keep the default selection of redhat.ins and click Continue.

16.9. Installing in an LPAR (Common Steps)

Once the installation program has started (if the red field behind the LPAR icon is disappearing, the installation program has begun), select the LPAR and double-click on Operating System Messages.
The initial installation start-up script asks you questions about your networking and DASD configurations. Red Hat Enterprise Linux has changed the limit for parameter file definitions and now accepts thirty-two (32) parameters. Any information not specified in the parameter file must be specified by answering the installation program questions.
Once all questions have been answered, you are ready to begin the core installation program, loader. To continue with the installation, refer to Chapter 17, Installing on IBM System z Systems for further instructions.

Note

If you install over a network with a Hard Drive Installation source you must perform a text mode installation.

16.10. Do You Have Enough Disk Space?

Nearly every modern-day operating system (OS) uses disk partitions, and Red Hat Enterprise Linux is no exception. When you install Red Hat Enterprise Linux, you may have to work with disk partitions.
The disk space used by Red Hat Enterprise Linux must be separate from the disk space used by other OSes you may have installed on your system.
For more information about disks and partition configuration, refer to Section 17.14.4, “Recommended Partitioning Scheme”.


[8] Direct Access Storage Devices (or DASDs) are hard disks that allow a maximum of three (3) partitions per DASD. For example, dasda has dasda[123].
[9] Using the zFCP driver over fiber and a dedicated switch, SCSI LUNs can be presented to the linux guest as if they were locally attached SCSI drives.

Chapter 17. Installing on IBM System z Systems

This chapter explains how to perform a Red Hat Enterprise Linux installation using the graphical, mouse-based installation program. The following topics are discussed:
  • Becoming familiar with the installation program's user interface
  • Starting the installation program
  • Selecting an installation method
  • Configuration steps during the installation (language, keyboard, mouse, partitioning, etc.)
  • Finishing the installation

17.1. The Graphical Installation Program User Interface

If you have used a graphical user interface (GUI) before, you are already familiar with this process; use your mouse to navigate the screens, click buttons, or enter text fields.
You can also navigate through the installation using the keyboard. The Tab key allows you to move around the screen, the Up and Down arrow keys to scroll through lists, + and - keys expand and collapse lists, while Space and Enter selects or removes from selection a highlighted item. You can also use the Alt+X key command combination as a way of clicking on buttons or making other screen selections, where X is replaced with any underlined letter appearing within that screen.

Note

While text mode installations are not explicitly documented, those using the text mode installation program can easily follow the GUI installation instructions. One thing to note is that manipulation of LVM (Logical Volume Management) disk volumes and the configuration of zFCP devices are only possible in graphical mode. In text mode it is only possible to view and accept the default LVM setup.

17.2. The Text Mode Installation Program User Interface

The Red Hat Enterprise Linux text mode installation program uses a screen-based interface that includes most of the on-screen widgets commonly found on graphical user interfaces. Figure 17.1, “Installation Program Widgets as seen in Disk Druid illustrates the screen that appears during the installation process.

Note

While text mode installations are not explicitly documented, those using the text mode installation program can easily follow the GUI installation instructions. One thing to note is that manipulation of LVM (Logical Volume Management) disk volumes is only possible in graphical mode. In text mode it is only possible to view and accept the default LVM setup.
Installation Program Widgets as seen in Disk Druid

Figure 17.1. Installation Program Widgets as seen in Disk Druid

Here is a list of the most important widgets shown in Figure 17.1, “Installation Program Widgets as seen in Disk Druid:
  • Text Widget — Text widgets are regions of the screen for the display of text. At times, text widgets may also contain other widgets, such as checkboxes. If a text widget contains more information than can be displayed in the space reserved for it, a scroll bar appears; if you position the cursor within the text widget, you can then use the Up and Down arrow keys to scroll through all the information available. Your current position is shown on the scroll bar by a # character, which moves up and down the scroll bar as you scroll.
  • Scroll Bar — Scroll bars appear on the side or bottom of a window to control which part of a list or document is currently in the window's frame. The scroll bar makes it easy to move to any part of a file.
  • Button Widget — Button widgets are the primary method of interacting with the installation program. You progress through the windows of the installation program by navigating these buttons, using the Tab and Enter keys. Buttons can be selected when they are highlighted.
  • Cursor — Although not a widget, the cursor is used to select (and interact with) a particular widget. As the cursor is moved from widget to widget, it may cause the widget to change color, or the cursor itself may only appear positioned in or next to the widget. Figure 17.1, “Installation Program Widgets as seen in Disk Druid, shows the cursor on the Edit button.

17.2.1. Using the Keyboard to Navigate

Navigation through the installation dialogs is performed through a simple set of keystrokes. To move the cursor, use the Left, Right, Up, and Down arrow keys. Use Tab, and Shift-Tab to cycle forward or backward through each widget on the screen. Along the bottom, most screens display a summary of available cursor positioning keys.
To "press" a button, position the cursor over the button (using Tab, for example) and press Space or Enter. To select an item from a list of items, move the cursor to the item you wish to select and press Enter. To select an item with a checkbox, move the cursor to the checkbox and press Space to select an item. To deselect, press Space a second time.
Pressing F12 accepts the current values and proceeds to the next dialog; it is equivalent to pressing the OK button.

Warning

Unless a dialog box is waiting for your input, do not press any keys during the installation process (doing so may result in unpredictable behavior).

17.3. Running the Installation Program

After following the steps outlined in Chapter 16, Steps to Get You Started for booting an LPAR or VM system, ssh to the configured Linux install system on the IBM System z.
Although the text mode installation program is run by default for most installations, you can optionally run the graphical installation program available for both VM and LPAR installations via the NFS installation method.

Note

If you have a slow network connection or prefer a text-based installation, do not set the DISPLAY= variable in the parm file. The text-based installation is similar to the graphical installation; however, the graphical installation offers more package selection details and other options not available in text-based installs. It is strongly recommended to use the graphical installation whenever possible.
To run the graphical installation, use a workstation that has an X Window System server or VNC client installed. Use an SSH client that allows X11 forwarding or a Telnet client. SSH is strongly recommended for its security features as well as its ability to forward X and VNC sessions. Enable X11 forwarding in your SSH client prior to connecting to the Linux image (the Linux guest running on z/VM).

17.3.1. Installation using X11 Forwarding

For example, to connect to the Linux image and display the graphical installation program using OpenSSH with X11 forwarding on a Linux workstation, type the following at the workstation shell prompt:
ssh -X linuxvm.example.com
The -X option enables X11 forwarding.
The graphical installation program cannot be started if your DNS or hostnames are not set correctly, or the Linux image is not allowed to open applications on your display. You can prevent this by setting a correct DISPLAY= variable. Add the parameter DISPLAY=workstationname:0.0 in the parameter file, replacing workstationname with the hostname of the client workstation connecting to the Linux Image. Allow the Linux image to connect to the workstation using the command xhost +linuxvm on the local workstation.
If the graphical installation via NFS does not automatically begin for you, verify the DISPLAY= variable settings in the parm file. If performing a VM installation, rerun the installation to load the new parm file on the reader. Additionally, make sure when performing an X11 forwarded display that the X server is started on the workstation machine. Finally, make sure either the NFS, FTP or HTTP protocols are selected, as all 3 methods support graphical installations.

17.3.2. Installation using VNC

If you are using VNC, a message on the workstation SSH terminal prompts you to start the VNC client viewer and details the VNC display specifications. Enter the specifications from the SSH terminal into the VNC client viewer and connect to the Linux image to begin the installation.
Once you have logged into the Linux image the loader will start the installation program.
When the loader starts, several screens appear for selecting the installation method.

17.4. Installing from a Hard Drive (DASD)

The Select Partition screen applies only if you are installing from a disk partition (that is, if you used the askmethod boot options and selected Hard Drive in the Installation Method dialog). This dialog allows you to name the disk partition and directory from which you are installing Red Hat Enterprise Linux. If you used the repo=hd boot option, you already specified a partition.
Enter the device name of the partition containing the Red Hat Enterprise Linux ISO images. This partition must be formatted with a ext2 or vfat filesystem, and cannot be a logical volume. There is also a field labeled Directory holding images.
If the ISO images are in the root (top-level) directory of a partition, enter a /. If the ISO images are located in a subdirectory of a mounted partition, enter the name of the directory holding the ISO images within that partition. For example, if the partition on which the ISO images is normally mounted as /home/, and the images are in /home/new/, you would enter /new/.
After you have identified the disk partition, the Welcome dialog appears.

17.5. Installing via NFS

The NFS dialog applies only if you are installing from an NFS server (if you selected NFS Image in the Installation Method dialog).
Enter the domain name or IP address of your NFS server. For example, if you are installing from a host named eastcoast in the domain example.com, enter eastcoast.example.com in the NFS Server field.
Next, enter the name of the exported directory. If you followed the setup described in Section 16.4, “Preparing for a Network Installation”, you would enter the directory /export/directory/.
If the NFS server is exporting a mirror of the Red Hat Enterprise Linux installation tree, enter the directory which contains the root of the installation tree. You will enter an Installation Key later on in the process which will determine which subdirectories are used to install from. If everything was specified properly, a message appears indicating that the installation program for Red Hat Enterprise Linux is running.
NFS Setup Dialog

Figure 17.2. NFS Setup Dialog

If the NFS server is exporting the ISO images of the Red Hat Enterprise Linux CD-ROMs, enter the directory which contains the ISO images.
Next, the Welcome dialog appears.

17.6. Installing via FTP

The FTP dialog applies only if you are installing from an FTP server (that is, if you used the askmethod boot options and selected FTP in the Installation Method dialog). This dialog allows you to identify the FTP server from which you are installing Red Hat Enterprise Linux. If you used the repo=ftp boot option, you already specified a server and path.
FTP Setup Dialog

Figure 17.3. FTP Setup Dialog

Enter the name or IP address of the FTP site you are installing from, and the name of the directory containing the variant/ directory for your architecture. For example, if the FTP site contains the directory /mirrors/redhat/arch/variant;/, enter /mirrors/redhat/arch/ (where arch is replaced with the architecture type of your system, such as i386, ia64, ppc, or s390x, and variant is the variant that you are installing, such as Client, Server, Workstation, etc.). If everything was specified properly, a message box appears indicating that files are being retrieved from the server.
Next, the Welcome dialog appears.

Note

You can save disk space by using the ISO images you have already copied to the server. To accomplish this, install Red Hat Enterprise Linux using ISO images without copying them into a single tree by loopback mounting them. For each ISO image:
mkdir discX
mount -o loop RHEL5-discX.iso discX
Replace X with the corresponding disc number.

17.7. Installing via HTTP

The HTTP dialog applies only if you are installing from an HTTP server (that is, if you used the askmethod boot option and selected HTTP in the Installation Method dialog). This dialog prompts you for information about the HTTP server from which you are installing Red Hat Enterprise Linux. If you used the repo=http boot option, you already specified a server and path.
Enter the name or IP address of the HTTP site you are installing from, and the name of the directory containing the variant/ directory for your architecture. For example, if the HTTP site contains the directory /mirrors/redhat/arch/variant/, enter /mirrors/redhat/arch/ (where arch is replaced with the architecture type of your system, such as i386, ia64, ppc, or s390x, and variant is the variant that you are installing, such as Client, Server, Workstation, etc.). If everything was specified properly, a message box appears indicating that files are being retrieved from the server.
HTTP Setup Dialog

Figure 17.4. HTTP Setup Dialog

Next, the Welcome dialog appears.

Note

You can save disk space by using the ISO images you have already copied to the server. To accomplish this, install Red Hat Enterprise Linux using ISO images without copying them into a single tree by loopback mounting them. For each ISO image:
mkdir discX
mount -o loop RHEL5-discX.iso discX
Replace X with the corresponding disc number.

17.8. Welcome to Red Hat Enterprise Linux

The Welcome screen does not prompt you for any input. From this screen you can access the Release Notes for Red Hat Enterprise Linux 5.11 by clicking on the Release Notes button.
Click on the Next button to continue.

17.9. Language Selection

Using your mouse, select a language to use for the installation (refer to Figure 17.5, “Language Selection”).
The language you select here will become the default language for the operating system once it is installed. Selecting the appropriate language also helps target your time zone configuration later in the installation. The installation program tries to define the appropriate time zone based on what you specify on this screen.
Language Selection

Figure 17.5. Language Selection

Once you select the appropriate language, click Next to continue.

17.10. Enter the Installation Number

Enter your Installation Number (refer to Figure 17.6, “Installation Number”). This number will determine the package selection set that is available to the installer. If you choose to skip entering the installation number you will be presented with a basic selection of packages to install later on.
Installation Number

Figure 17.6. Installation Number

17.11. Disk Partitioning Setup

Partitioning allows you to divide your storage drive(s) into isolated sections, where each section behaves as its own drive. Partitioning is particularly useful if you run multiple operating systems, or wish to enforce a logical or functional distinction between your storage partitions (such as a /home partition that persistently contains user information).
On this screen you can choose to create the default layout or choose to manual partition using the 'Create custom layout' option of Disk Druid.
The first three options allow you to perform an automated installation without having to partition your drive(s) yourself. If you do not feel comfortable with partitioning your system, it is recommended that you do not choose to create a custom layout and instead let the installation program partition for you.
You can configure an zFCP LUN for installation, or disable a dmraid device from this screen by clicking on the 'Advanced storage configuration' button. For more information refer to Section 17.12, “ Advanced Storage Options ”.

Warning

The default layout uses all devices made available to the installer. This includes any temporary storage devices such as vdisks or tdisks. If temporary storage devices are used with the default layout, the system might become inaccessible when these devices are redefined and the device contents are lost (for example, on logoff and relogon of z/VM guests). Review the partition layout and if temporary devices are included, go back and choose Create custom layout to exclude these devices from being used for permanent system data.

Warning

The Update Agent downloads updated packages to /var/cache/yum/ by default. If you partition the system manually, and create a separate /var/ partition, be sure to create the partition large enough (3.0 GB or more) to download package updates.
Disk Partitioning Setup

Figure 17.7. Disk Partitioning Setup

If you choose to create a custom layout using Disk Druid, refer to Section 17.14, “Partitioning Your System”.

Warning

If you receive an error after the Disk Partitioning Setup phase of the installation saying something similar to:
"The partition table on device dasda was unreadable. To create new partitions it must be initialized, causing the loss of ALL DATA on this drive."
you may not have a partition table on that drive or the partition table on the drive may not be recognizable by the partitioning software used in the installation program.
No matter what type of installation you are performing, backups of the existing data on your systems should always be made.

Important

To install Red Hat Enterprise Linux on a network device accessible through multiple paths, deselect all local storage in the Select the drive(s) to use for this installation window, and select a device labeled mapper/mpath instead.
Note that migrating the root file system of an existing Red Hat Enterprise Linux installation from single path storage to multipath storage is not supported. You must perform a new installation to move the root file system to a multipath storage device. Therefore you should plan your installation accordingly. See https://access.redhat.com/site/solutions/66501 for more information.

17.12.  Advanced Storage Options

17.12.1. FCP Devices

FCP (Fibre Channel protocol) devices enable IBM System z to use SCSI devices rather than DASD devices. FCP (Fibre Channel protocol) devices provide a switched fabric topology that enables zSeries systems to use SCSI LUNs as disk devices in addition to traditional DASD devices.
Typically, an operating system is loaded, and the automatic probing and defining of hardware is done by the OS. However, because of the flexibility of configurations associated with FCP, IBM System z requires that any FCP (Fibre Channel protocol) device be entered manually (either in the installation program interactively, or specified as unique parameter entries in the CMS conf file) in order for the installation program to recognize the hardware. The values entered here are unique to each site in which they are setup.

Note

Interactive creation of a zFCP device is only possible in the graphical mode installer. It is not possible to interactively configure a zFCP device in a text-only install.
Each value entered should be verified as correct, as any mistakes made may cause the system not to operate properly.
For more information on these values, refer to the hardware documentation that came with your system and check with the system administrator who has setup the network for this system.
Advanced Storage Options

Figure 17.8. Advanced Storage Options

To configure a Fiber Channel Protocol SCSI device invoke the 'Add FCP device' dialog by selecting 'Add ZFCP LUN' and clicking on the 'Add Drive' button. Fill in the details for the 16 bit device number, 64 bit World Wide Port Number (WWPN) and 64 bit FCP LUN. Click the 'Add' button to attempt connection to the FCP device using this information.
Configure FCP Device

Figure 17.9. Configure FCP Device

The newly added device should then be present and usable during the Disk Druid portion of the installation.
Configure FCP Device

Figure 17.10. Configure FCP Device

Note

The installer requires that at least one ECKD DASD be defined. In the situation where a SCSI-only installation is desired a DASD= parameter should be entered into the CMS conf file with a non-existent device number. This will satisfy Anaconda's requirement for a defined ECKD DASD, while resulting in a SCSI-only environment.

17.13. Create Default Layout

Create default layout allows you to have some control concerning what data is removed (if any) from your system. Your options are:
  • Remove all partitions on selected drives and create default layout — select this option to remove all partitions on your hard drive(s) (this includes partitions created by other operating systems such as z/VM or z/OS).

    Warning

    If you select this option, all data on the selected DASD and SCSI storage drive(s) is removed by the installation program. Do not select this option if you have information that you want to keep on the storage drive(s) where you are installing Red Hat Enterprise Linux.
  • Remove Linux partitions on selected drives and create default layout — select this option to remove only Linux partitions (partitions created from a previous Linux installation). This does not remove other partitions you may have on your storage drive(s) (such as z/VM or z/OS partitions).
  • Use free space on selected drives and create default layout — select this option to retain your current data and partitions, assuming you have enough free space available on your storage drive(s).
Create Default Layout

Figure 17.11. Create Default Layout

Using your mouse, choose the storage drive(s) on which you want Red Hat Enterprise Linux to be installed. If you have two or more drives, you can choose which drive(s) should contain this installation. Unselected drives, and any data on them, are not touched.

Warning

It is always a good idea to back up any data that you have on your systems. For example, if you are upgrading or creating a dual-boot system, you should back up any data you wish to keep on your drive(s). Mistakes do happen and can result in the loss of all your data.
To review and make any necessary changes to the partitions created by automatic partitioning, select the Review option. After selecting Review and clicking Next to move forward, the partitions created for you in Disk Druid appear. You can make modifications to these partitions if they do not meet your needs.
Click Next once you have made your selections to proceed.

17.14. Partitioning Your System

If you chose to create a custom layout, you must tell the installation program where to install Red Hat Enterprise Linux. This is done by defining mount points for one or more disk partitions in which Red Hat Enterprise Linux is installed.
Partitioning with Disk Druid

Figure 17.12.  Partitioning with Disk Druid

The partitioning tool used by the installation program is Disk Druid. With the exception of certain esoteric situations, Disk Druid can handle the partitioning requirements for a typical installation.

17.14.1. Graphical Display of DASD Device(s)

Disk Druid offers a graphical representation of your DASD device(s).
Using your mouse, click once to highlight a particular field in the graphical display. Double-click to edit an existing partition or to create a partition out of existing free space.
Above the display, you can review the Drive name (such as /dev/dasda), the Geom (which shows the hard disk's geometry and consists of three numbers representing the number of cylinders, heads, and sectors as reported by the hard disk), and the Model of the hard drive as detected by the installation program.
Finally, note which device is associated with /boot. The kernel files and bootloader sector will be associated with this device. For most common cases, the first DASD or SCSI LUN will be used, but for some unusual cases, this may not be the case. The device number will be used when re-ipling the post-installed system.

17.14.2. Disk Druid's Buttons

These buttons control Disk Druid's actions. They are used to change the attributes of a partition (for example the file system type and mount point) and also to create RAID devices. Buttons on this screen are also used to accept the changes you have made, or to exit Disk Druid. For further explanation, take a look at each button in order:
  • Edit: Used to modify attributes of the partition currently selected in the Partitions section. Selecting Edit opens a dialog box. Some or all of the fields can be edited, depending on whether the partition information has already been written to disk.
  • RAID: Used to provide redundancy to any or all disk partitions. It should only be used if you have experience using RAID. To read more about RAID, see the Red Hat Enterprise Linux Deployment Guide.
    To make a RAID device, you must first create software RAID partitions. Once you have created two or more software RAID partitions, select RAID to join the software RAID partitions into a RAID device.

17.14.3. Partition Fields

Above the partition hierarchy are labels which present information about the partitions you are creating. The labels are defined as follows:
  • Device: This field displays the partition's device name.
  • Mount Point/RAID/Volume: A mount point is the location within the directory hierarchy at which a volume exists; the volume is "mounted" at this location. This field indicates where the partition is mounted. If a partition exists, but is not set, then you need to define its mount point. Double-click on the partition or click the Edit button.
  • Type: This field shows the partition's file system type (for example, ext2, ext3, or vfat).
  • Format: This field shows if the partition being created will be formatted.
  • Size (MB): This field shows the partition's size (in MB).
  • Start: This field shows the cylinder on your hard drive where the partition begins.
  • End: This field shows the cylinder on your hard drive where the partition ends.
Hide RAID device/LVM Volume Group members: Select this option if you do not want to view any RAID device or LVM Volume Group members that have been created.

17.14.4. Recommended Partitioning Scheme

Configuring efficient swap space for Linux on System z is a complex task. It very much depends on the specific environment and should be tuned to the actual system load.
Refer to the following resources for more information and to guide your decision:

17.14.5. Editing Partitions

To edit a partition, select the Edit button or double-click on the existing partition.

Note

If the partition already exists on your disk, you can only change the partition's mount point. To make any other changes, you must delete the partition and recreate it.

17.15. Network Configuration

If you do not have a network device, this screen does not appear during your installation and you should advance to Section 17.16, “Time Zone Configuration”.
Network Configuration

Figure 17.13. Network Configuration

The installation program automatically detects any network devices you have and displays them in the Network Devices list.
When you have selected a network device, click Edit. From the Edit Interface dialog, you can choose to configure the IP address and Netmask (for IPv4 - Prefix for IPv6) of the device to use DHCP or to use static settings. If you do not have DHCP client access or you are unsure what to provide here, contact your network administrator.

Note

DHCP should not be chosen for qdio/qeth devices that are configured with OSA layer 3 support. Layer 3 does not provide MAC address or Address Resolution Protocol (ARP) abilities and so can not be used with network services that require them.
Editing a Network Device

Figure 17.14. Editing a Network Device

Note

Do not use the numbers as seen in this sample configuration. These values will not work for your own network configuration. If you are not sure what values to enter, contact your network administrator for assistance.
If you have a hostname (fully qualified domain name) for the network device, you can choose to have DHCP (Dynamic Host Configuration Protocol) automatically detect it or you can manually enter the hostname in the field provided.
Finally, if you entered the IP and Netmask information manually, you may also enter the Gateway address and the Primary and Secondary DNS addresses.

17.16. Time Zone Configuration

Set your time zone by selecting the city closest to your computer's physical location. Click on the map to zoom in to a particular geographical region of the world.
From here there are two ways for you to select your time zone:
  • Using your mouse, click on the interactive map to select a specific city (represented by a yellow dot). A red X appears indicating your selection.
  • You can also scroll through the list at the bottom of the screen to select your time zone. Using your mouse, click on a location to highlight your selection.
Configuring the Time Zone

Figure 17.15. Configuring the Time Zone

Select System Clock uses UTC if you know that your system is set to UTC.

Note

To change your time zone configuration after you have completed the installation, use the Time and Date Properties Tool.
Type the system-config-date command in a shell prompt to launch the Time and Date Properties Tool. If you are not root, it prompts you for the root password to continue.
To run the Time and Date Properties Tool as a text-based application, use the command timeconfig.

17.17. Set Root Password

Setting up a root account and password is one of the most important steps during your installation. Your root account is similar to the administrator account used on Windows NT machines. The root account is used to install packages, upgrade RPMs, and perform most system maintenance. Logging in as root gives you complete control over your system.

Note

The root user (also known as the superuser) has complete access to the entire system; for this reason, logging in as the root user is best done only to perform system maintenance or administration.
Root Password

Figure 17.16. Root Password

Use the root account only for system administration. Create a non-root account for your general use and su - to root when you need to fix something quickly. These basic rules minimize the chances of a typo or an incorrect command doing damage to your system.

Note

To become root, type su - at the shell prompt in a terminal window and then press Enter. Then, enter the root password and press Enter.
The installation program prompts you to set a root password[10] for your system. You cannot proceed to the next stage of the installation process without entering a root password.
The root password must be at least six characters long; the password you type is not echoed to the screen. You must enter the password twice; if the two passwords do not match, the installation program asks you to enter them again.
You should make the root password something you can remember, but not something that is easy for someone else to guess. Your name, your phone number, qwerty, password, root, 123456, and anteater are all examples of bad passwords. Good passwords mix numerals with upper and lower case letters and do not contain dictionary words: Aard387vark or 420BMttNT, for example. Remember that the password is case-sensitive. If you write down your password, keep it in a secure place. However, it is recommended that you do not write down this or any password you create.

Note

Do not use one of the example passwords offered in this manual. Using one of these passwords could be considered a security risk.

Note

To change your root password after you have completed the installation, use the Root Password Tool.
Type the system-config-rootpassword command in a shell prompt to launch the Root Password Tool. If you are not root, it prompts you for the root password to continue.

17.18. Package Group Selection

Now that you have made most of the choices for your installation, you are ready to confirm the default package selection or customize packages for your system.
The Package Installation Defaults screen appears and details the default package set for your Red Hat Enterprise Linux installation. This screen varies depending on the version of Red Hat Enterprise Linux you are installing.
If you choose to accept the current package list, skip ahead to Section 17.19, “Preparing to Install”.
To customize your package set further, select the Customize now option on the screen. Clicking Next takes you to the Package Group Selection screen.
You can select package groups, which group components together according to function (for example, X Window System and Editors), individual packages, or a combination of the two.

Note

Users of IBM System z who want support for developing or running legacy 31-bit applications are encouraged to select the Compatibility Arch Support and Compatibility Arch Development Support packages to install architecture specific support for their systems.
To select a component, click on the checkbox beside it (refer to Figure 17.17, “Package Group Selection”).
Package Group Selection

Figure 17.17. Package Group Selection

Select each component you wish to install.
Once a package group has been selected, if optional components are available you can click on Optional packages to view which packages are installed by default, and to add or remove optional packages from that group. If there are no optional components this button will be disabled.
Package Group Details

Figure 17.18. Package Group Details

17.19. Preparing to Install

17.19.1. Preparing to Install

A screen preparing you for the installation of Red Hat Enterprise Linux now appears.
For your reference, a complete log of your installation can be found in /root/install.log once you reboot your system.

Warning

If, for some reason, you would rather not continue with the installation process, this is your last opportunity to safely cancel the process and reboot your machine. Once you press the Next button, partitions are written and packages are installed. If you wish to abort the installation, you should close your SSH session and re-IPL the machineeboot now before any existing information on any hard drive is rewritten.
To cancel this installation process, close your SSH session and re-IPL the system using your 3270 terminal emulator.

17.20. Installing Packages

At this point there is nothing left for you to do until all the packages have been installed. How quickly this happens depends on the number of packages you have selected and your computer's speed.

17.21. Installation Complete

Congratulations! Your Red Hat Enterprise Linux installation is now complete!
The installation program prompts you to prepare your system for reboot.
Once the installation is complete, you must IPL (boot) from either the DASD or SCSI LUN where the /boot partition for Red Hat Enterprise Linux has been installed.
For example, using dasd at device 200 on the 3270 console you may issue the command #cp i 200. Often, especially in DASD only environments where automatic partitioning (clearing data from all partitions) was chosen, the first dasd (dasda) is where the /boot partition is located.
Using /boot on a SCSI LUN in a z/VM guest account, it may be necessary to provide WWPN and LUN information through which a zFCP device can ipl. As an example,
#CP SET LOADDEV PORTNAME 50050763 FCCD9689 LUN 83030000 00000000
could be used to provide zFCP routing information to a zFCP device (where 0x50050763FCCD9689 is the example WWPN, and 8303 is the SCSI LUN). Then the zFCP device information can be queried and used to start the IPL:
#cp q v fcp
After querying this information the zFCP device (4322 in this example) could be ipl-ed with a command like:
#cp ipl 4322
For LPAR-based installations, the HMC console may be used to issue a load command to the LPAR, specifying the particular DASD or SCSI LUN and zFCP WWPN where the /boot partition is located.

Note

For guest accounts using z/VM, assuming you want to disconnect from the 3270 console without halting the linux guest, use #cp disc instead of #cp logout or #cp log. This allows for the virtual system running Red Hat Enterprise Linux for IBM System z to continue even when not connected to the 3270 console.
Following IPLing the installed Red Hat Enterprise Linux OS, you may log on to the system via ssh. It is important to note that the only place you can log in as root is from the 3270 or from other devices as listed in /etc/securetty.
The first time you start your Red Hat Enterprise Linux system in a graphical environment, the Setup Agent may be manually started, which guides you through the Red Hat Enterprise Linux configuration. Using this tool, you can set your system time and date, install software, register your machine with Red Hat Network, and more. The Setup Agent lets you configure your environment at the beginning, so that you can get started using your Red Hat Enterprise Linux system quickly.
For information on registering your Red Hat Enterprise Linux subscription, refer to Chapter 25, Register Your System and Apply Subscriptions.


[10] A root password is the administrative password for your Red Hat Enterprise Linux system. You should only log in as root when needed for system maintenance. The root account does not operate within the restrictions placed on normal user accounts, so changes made as root can have implications for your entire system.

Chapter 18. Removing Red Hat Enterprise Linux

To remove from the S/390 you can either remove the DASD allocation from the VM or you can start the installation program and re-format all of the DASD partitions. Instead of selecting OK you will select Cancel to exit the installation program.

Chapter 19. Sample Parameter Files

The IBM System z architectures use a special parameter file to set up networking before the installation program (anaconda) can be started. This section describes the contents of the parameter file.
The parameter file has a limit of 32 total parameters. To accommodate limitations of the parameter files, a new configuration file on a CMS DASD should be used to configure the initial network setup and the DASD specification. The .parm file should contain the real kernel parameters, such as root=/dev/ram0 ro ip=off ramdisk_size=40000, and single parameters which are not assigned to variables, such as vnc. Two new parameters which point the installation program at the new configuration file need to be added to the .parm file. They are CMSDASD and CMSCONF .
CMSDASD=cmsdasd_address
Where cmsdasd_address represents the list of the device ID of the CMS DASD device which contains the configuration file. This is usually the CMS user's 'A' disk. This option is applicable only for users who have a CMS formatted disk (z/VM) available.
For example: CMSDASD=191
CMSCONFFILE=configuration_file
Where configuration_file represents the name of the configuration file. This value must be specified in lower case. It is specified in a Linux style file name format. The CMS file REDHAT CONF is specified as redhat.conf. This option is applicable only for users who have a CMS formatted disk (z/VM) available.
For example: CMSCONFFILE=redhat.conf
DASD=dasd-list
Where dasd-list represents the list of DASD devices to be used by Red Hat Enterprise Linux.
Although automatic probing for DASDs is done if this parameter is omitted, it is highly recommended to include the DASD= parameter, as the device numbers (and therefore the device names) can vary when a new DASD is added to the guest. This can result in an unusable system.
For example: DASD=0.0.0100,0.0201-0.0.0204
The following parameters are required to set up networking:
SUBCHANNELS=
Provides required device bus IDs for the various network interfaces.
qeth: SUBCHANNELS="read_device_bus_id,write_device_bus_id,
      data_device_bus_id"
lcs: SUBCHANNELS="read_device_bus_id,write_device_bus_id"
Due to the length of the qeth command line, it has been broken into two lines.

Note

The CTC, and NETIUCV drivers have been deprecated and are no longer supported in Red Hat Enterprise Linux.
For example (a sample qeth SUBCHANNEL statement):
SUBCHANNELS=0.0.0600,0.0.0601,0.0.0602
The following parameters are optional:
HOSTNAME=string
Where string is the hostname of the newly-installed Linux guest.
NETTYPE=type
Where type must be one of the following: qeth or lcs.
IPADDR=IP
Where IP is the IP address of the new Linux guest.
NETWORK=network
Where network is the address of your network.
NETMASK=netmask
Where netmask is the netmask.
BROADCAST=broadcast
Where broadcast is the broadcast address.
GATEWAY=gw
Where gw is the gateway-IP for your eth device.
MTU=mtu
Where mtu is the Maximum Transmission Unit (MTU) for this connection.
DNS=server1:server2:additional_server_terms:serverN
Where server1:server2:additional_server_terms:serverN is a list of DNS servers, separated by colons. For example:
DNS=10.0.0.1:10.0.0.2
SEARCHDNS=domain1:domain2:additional_dns_terms:domainN
Where domain1:domain2:additional_dns_terms:domainN is a list of the search domains, separated by colons. For example:
SEARCHDNS=example.com:example.org
PORTNAME=osa_portname | lcs_portnumber
This variable supports OSA devices operating in qdio mode or in non-qdio mode.
When using qdio mode: osa_portname is the portname specified on the OSA device when operating in qeth mode. PORTNAME is only required for z/VM 4.3 or older without APARs VM63308 and PQ73878.
When using non-qdio mode: lcs_portnumber is used to pass the relative port number as integer in the range of 0 through 15.
PORTNO=portnumber
When installing under z/VM, you can add either PORTNO=0 (to use port 0) or PORTNO=1 (to use port 1) to the CMS configuration file to avoid being prompted for the mode.
The PORTNO= setting also works on LPAR, but you must place it directly in the parmfile rather than the CMS configuration file.
LAYER2=
Add either LAYER2=0 or LAYER2=1 to the CMS configuration file to make the mode persistent when installing on a System z guest.
Use LAYER2=0 when the OSA is in layer 3 mode, and LAYER2=1 when the OSA is in layer 2 mode.
VSWITCH=
When specifying LAYER2=1, you can also specify VSWITCH=1 when connecting to a VSWITCH, or VSWITCH=0 when connecting directly to the OSA.
MACADDR=MAC_address
When specifying LAYER2=1 and a VSWITCH is not in use, you can use this parameter to specify the MAC address in the CMS configuration file.
FCP_* (FCP_1, FCP_2, ...)
These variables can be used on systems with FCP devices to preconfigure the FCP setup (these can be changed during the installation).
Use the following samples as a guide to formatting proper parameter files.
Sample file with minimally required parameters:
root=/dev/ram0 DASD=200

Note

The installation program prompts the user for any required parameters not specified in the parameter file.
Sample file configuring a QETH networking device:
Example of redhat.parm file:
root=/dev/ram0 ro ip=off ramdisk_size=40000
CMSDASD=191 CMSCONFFILE=redhat.conf
vnc
Example of redhat.conf file (pointed to by CMSCONFFILE in redhat.parm)
DASD=200
HOSTNAME="foobar.systemz.example.com"
DASD="200-203"
NETTYPE="qeth"
IPADDR="192.168.17.115"
SUBCHANNELS="0.0.0600,0.0.0601,0.0.0602"
PORTNAME="FOOBAR"
NETWORK="192.168.17.0"
NETMASK="255.255.255.0"
BROADCAST="192.168.17.255"
SEARCHDNS="example.com:systemz.example.com"
GATEWAY="192.168.17.254"
DNS="192.168.17.1"
MTU="4096"

Chapter 20. Additional Boot Options

This section discusses additional boot and kernel boot options available for the Red Hat Enterprise Linux installation program.
To use any of the boot options presented here, type the command you wish to invoke at the installation boot: prompt.
You can also store kernel boot options for the z/IPL boot loader in the zipl.conf file, either by editing the file manually or using the zipl tool.

Important

Where kernel parameters use nested quotation marks, the required order in Red Hat Enterprise Linux is double quote marks for the outer set and single quote marks for the inner set. For example, parameters="vmhalt='LOGOFF'" is correct, while parameters='vmhalt="LOGOFF"' is not correct and may lead to unexpected behavior.

boot time command arguments

askmethod
this command asks you to select the installation method you would like to use when booting from the Red Hat Enterprise Linux CD-ROM.
dd=url
this argument causes the installation program to prompt you to use a driver image from a specified HTTP, FTP, or NFS network address.
display=ip:0
this command allows remote display forwarding. In this command, ip should be replaced with the IP address of the system on which you want the display to appear.
On the system you want the display to appear on, you must execute the command xhost +remotehostname, where remotehostname is the name of the host from which you are running the original display. Using the command xhost +remotehostname limits access to the remote display terminal and does not allow access from anyone or any system not specifically authorized for remote access.
mediacheck
this command gives you the option of testing the integrity of the install source (if an ISO-based method). this command works with the CD, DVD, hard drive ISO, and NFS ISO installation methods. Verifying that the ISO images are intact before you attempt an installation helps to avoid problems that are often encountered during an installation.
mpath
enables multipath support.

Important

If you install Red Hat Enterprise Linux 5.11 on a network storage device accessible through multiple paths, you must boot the installation process with this option. If you do not specify this option at boot time, installation will fail, or the system will fail to boot after installation completes.
noeject
do not eject optical discs after installation. This option is useful in remote installations where it is difficult to close the tray afterwards.
noprobe
this command disables hardware detection and instead prompts the user for hardware information.
rescue
this command runs rescue mode. Refer to Chapter 27, Basic System Recovery for more information about rescue mode.
text
this command disables the graphical installation program and forces the installation program to run in text mode.
vnc
this command allows you to install from a VNC server.
vncpassword=
this command sets the password used to connect to the VNC server.
noipv6
this command disables the default selection of ipv6 options during the installer stage 1 processing. Ipv6 settings may still be made manually if this option is specified, but the default behavior will be that Ipv6 settings are not enabled.
cmdline
The 3270 console (most often used during installation on IBM System z) does not recognize terminal formatting entries common to most unix-style terminals. Specifying this option changes the behavior of anaconda during kickstart installations so that console output on the 3270 is much better. This option should not be used for regular, interactive installations.
RUNKS=1
This option is used to specify (usually in conjunction with the cmdline option) kickstart installation for IBM System z.

Chapter 21. Troubleshooting Installation on an IBM System z System

This appendix discusses some common installation problems and their solutions.

21.1. You are Unable to Boot Red Hat Enterprise Linux

21.1.1. Is Your System Displaying Signal 11 Errors?

A signal 11 error, commonly know as a segmentation fault, means that the program accessed a memory location that was not assigned to it. A signal 11 error may be due to a bug in one of the software programs that is installed, or faulty hardware.
Ensure that you have the latest installation updates and images from Red Hat. Review the online errata to see if newer versions are available.

21.2. Trouble During the Installation

21.2.1. No devices found to install Red Hat Enterprise Linux Error Message

If you receive an error message stating No devices found to install Red Hat Enterprise Linux, then there may be an issue with your DASD devices. If you encounter this error, add the DASD=<disks> parameter to your parm file (where disks is the DASD range reserved for installation) and start the install again.
Additionally, make sure you format the DASDs using the dasdfmt command within a Linux root shell, instead of formatting the DASDs using CMS.

21.2.2. Trouble with Partition Tables

If you receive an error after the Disk Partitioning Setup (Section 17.11, “Disk Partitioning Setup”) phase of the installation saying something similar to
The partition table on device hda was unreadable. To create new partitions it must be initialized, causing the loss of ALL DATA on this drive.
you may not have a partition table on that drive or the partition table on the drive may not be recognizable by the partitioning software used in the installation program.
No matter what type of installation you are performing, backups of the existing data on your systems should always be made.

21.2.3. Other Partitioning Problems

If you are using Disk Druid to create partitions, but cannot move to the next screen, you probably have not created all the partitions necessary for Disk Druid's dependencies to be satisfied.
You must have the following partitions as a bare minimum:
  • A / (root) partition
  • A <swap> partition of type swap

Note

When defining a partition's type as swap, do not assign it a mount point. Disk Druid automatically assigns the mount point for you.

21.2.4. Are You Seeing Python Errors?

During some upgrades or installations of Red Hat Enterprise Linux, the installation program (also known as anaconda) may fail with a Python or traceback error. This error may occur after the selection of individual packages or while trying to save the upgrade log in the /tmp/directory. The error may look similar to:
Traceback (innermost last):
File "/var/tmp/anaconda-7.1//usr/lib/anaconda/iw/progress_gui.py", line 20, in run
rc = self.todo.doInstall ()    
File "/var/tmp/anaconda-7.1//usr/lib/anaconda/todo.py", line 1468, in doInstall 
self.fstab.savePartitions ()    
File "fstab.py", line 221, in savePartitions      
sys.exit(0)  
SystemExit: 0   
Local variables in innermost frame:  
self: <fstab.GuiFstab instance at 8446fe0>  
sys: <module 'sys' (built-in)>  
ToDo object:  (itodo  ToDo  p1  (dp2  S'method'  p3  (iimage  CdromInstallMethod  
p4  (dp5  S'progressWindow'  p6   <failed>
This error occurs in some systems where links to /tmp/ are symbolic to other locations or have been changed since creation. These symbolic or changed links are invalid during the installation process, so the installation program cannot write information and fails.
If you experience such an error, first try to download any available errata for anaconda. Errata can be found at:
http://www.redhat.com/support/errata/
The anaconda website may also be a useful reference and can be found online at:
http://fedoraproject.org/wiki/Anaconda
You can also search for bug reports related to this problem. To search Red Hat's bug tracking system, go to:
http://bugzilla.redhat.com/bugzilla/
Finally, if you are still facing problems related to this error, register your product and contact our support team. To register your product, go to:
http://www.redhat.com/apps/activate/

21.3. Problems After Installation

21.3.1. Remote Graphical Desktops and XDMCP

If you have installed the X Window System and would like to log in to your Red Hat Enterprise Linux system using a graphical login manager, enable the X Display Manager Control Protocol (XDMCP). This protocol allows users to remotely log in to a desktop environment from any X Window System compatible client (such as a network-connected workstation or X terminal). To enable remote login using XDMCP, edit the following line in the /etc/gdm/custom.conf file on the Red Hat Enterprise Linux system with a text editor such as vi or nano:
Add the line Enable=true, save the file, and exit the text editor. Switch to runlevel 5 to start the X server:
/sbin/init 5
From the client machine, start remote X session using X. For example:
X :1 -query s390vm.example.com
The command connects to the remote X server via XDMCP (replace s390vm.example.com with the hostname of the remote X server) and displays the remote graphical login screen on display :1 of the client system (usually accessible by using the Ctrl-Alt-F8 key combination).
You may also access remote desktop sessions using a nested X server, which opens the remote desktop as a window in your current X session. Xnest allows users to open a remote desktop nested within their local X session. For example, run Xnest using the following command, replacing s390vm.example.com with the hostname of the remote X server:
Xnest :1 -query s390vm.example.com

21.3.2. Problems When You Try to Log In

If you did not create a user account in the Setup Agent, log in as root and use the password you assigned to root.
If you cannot remember your root password, boot your system as linux single.
Once you have booted into single user mode and have access to the # prompt, you must type passwd root, which allows you to enter a new password for root. At this point you can type shutdown -r now to reboot the system with the new root password.
If you cannot remember your user account password, you must become root. To become root, type su - and enter your root password when prompted. Then, type passwd <username>. This allows you to enter a new password for the specified user account.
If the graphical login screen does not appear, check your hardware for compatibility issues. The Hardware Compatibility List can be found at:
	http://hardware.redhat.com/hcl/

21.3.3. Your Printer Does Not Work

If you are not sure how to set up your printer or are having trouble getting it to work properly, try using the Printer Configuration Tool.
Type the system-config-printer command at a shell prompt to launch the Printer Configuration Tool. If you are not root, it prompts you for the root password to continue.

21.3.4. Apache-based httpd service/Sendmail Hangs During Startup

If you are having trouble with the Apache-based httpd service or Sendmail hanging at startup, make sure the following line is in the /etc/hosts file:
127.0.0.1  localhost.localdomain  localhost

Chapter 22. Additional Information for IBM System z Users

22.1. The sysfs File System

The Linux 2.6 kernel introduced the sysfs file system. The sysfs file system is described as a union of the proc, devfs, and devpty file systems. The sysfs file system enumerates the devices and busses attached to the system into a file system hierarchy that can be accessed from user space. It is designed to handle the device and driver specific options that have previously resided in /proc/, and encompass the dynamic device addition previously offered by devfs.
The sysfs file system is mounted at /sys/ and contains directories that organize the devices attached to the system in several different ways. The /sysfs/ subdirectories include:
  1. The /devices/ directory
    This directory contains the /css0/ directory. Its subdirectories represent all the subchannels detected by the Linux kernel. Subchannel directories are named in the form 0.0.nnnn where nnnn is the subchannel number in hex between 0000 and ffff. Subchannel directories in turn contain status files and another subdirectory which represents the actual device. The device directory is named 0.0.xxxx where xxxx is the unit address for the device. The /devices/ directory also contains status information as well as configuration options for the device.
  2. The /bus/ directory
    This contains a /ccw/ subdirectory and a /ccwgroup/ subdirectory. CCW devices are accessed using channel command words. Devices in the /ccw/ directory only use one subchannel on the mainframe channel subsystem. CCW group devices are also accessed with channel command words, but they use more than one subchannel per device. For example, a 3390-3 DASD device uses one subchannel, while a QDIO network connection for an OSA adapter uses three subchannels. The /ccw/ and the /ccwgroup/ directories both contain directories called devices and drivers:
    The /devices/ directory contains a symbolic link to the device directories in the /sys/devices/css0/ directory.
    The /drivers/ directory contains directories for each device driver currently loaded on the system. Drivers associated with devices such as dasd, console, qeth, and zfcp have directory entries here. The /driver/ directory contains settings for the device driver, as well as symbolic links to the devices it is using (in the /sys/devices/css0/ directory).
  3. The /class/ directory
    This contains directories that group together similar devices such as ttys, SCSI tape drives, network devices, and other miscellaneous devices.
  4. The /block/ directory
    This directory contains directories for each of the block devices on the system. These are mostly disk type devices such as real DASD, loopback devices, and software raid block devices. The noticeable difference between older Linux systems and ones that use sysfs is the need to refer to devices by their sysfs name. On a 2.4 kernel image, the zFCP driver was passed as its device addresses. On the 2.6 Kernel image system the driver is passed as 0.0.1600.

22.2. Using the zFCP Driver

During the initial installation, you are prompted to enter SCSI/FCP information. If this information is entered, it creates the /etc/zfcp.conf file which contains your SCSI configuration. It also adds the line alias scsi_hostadapter zFCP to /etc/modprobe.conf. This loads the required zFCP modules.
# cat /etc/zfcp.conf
0.0.010a 0x01 0x5005076300c18154 0x00 0x5719000000000000

# cat /etc/modprobe.conf
alias eth0 qeth
options dasd_mod dasd=201,4b2e
alias scsi_hostadapter zfcp
If no SCSI devices were defined during the initial installation, the following example demonstrates how to add one manually:
# cd /lib/modules/2.6.7-1.451.2.3/kernel/drivers/s390/scsi
# modprobe zfcp

# lsmod
Module                  Size  Used by
zfcp                  221460  0 [permanent]
autofs4                39944  0
qeth                  166288  0
qdio                   60240  3 zfcp,qeth
ccwgroup               25344  1 qeth
ipt_REJECT             23552  1
ipt_state              18944  5
ip_conntrack           57904  1 ipt_state
iptable_filter         19712  1
ip_tables              37888  3 ipt_REJECT,ipt_state,iptable_filter
sd_mod                 39688  0
scsi_mod              182904  2 zfcp,sd_mod
dm_mod                 86408  0
ext3                  179056  2
jbd                    92720  1 ext3
dasd_fba_mod           25344  0
dasd_eckd_mod          77056  4
dasd_mod               85328  6 dasd_fba_mod,dasd_eckd_mod

# cd /sys/bus/ccw/drivers/zfcp/0.0.010a

# echo 1 > online
# cat online
1

# echo 0x5005076300c18154 > /sys/bus/ccw/drivers/zfcp/0.0.010a/port_add
# ls
0x5005076300c18154  failed            lic_version    s_id
availability        fc_link_speed     nameserver     status
card_version        fc_service_class  online         wwnn
cmb_enable          fc_topology       port_add       wwpn
cutype              hardware_version  port_remove
detach_state        host2             scsi_host_no
devtype             in_recovery       serial_number

# cd /sys/bus/ccw/drivers/zfcp/0.0.010a/0x5005076300c18154
# echo 0x5719000000000000 > unit_add
# ls
0x5719000000000000  d_id    in_recovery  status    unit_remove
detach_state        failed  scsi_id      unit_add  wwnn

# cat /sys/bus/ccw/drivers/zfcp/0.0.010a/scsi_host_no
0x0
# cat /sys/bus/ccw/drivers/zfcp/0.0.010a/0x5005076300c18154/scsi_id
0x1
# cat \
/sys/bus/ccw/drivers/zfcp/0.0.010a/0x5005076300c18154/0x5719000000000000/scsi_lun
0x0

# cat /sys/bus/scsi/devices/0\:0\:1\:0/hba_id
0.0.010a
# cat /sys/bus/scsi/devices/0\:0\:1\:0/wwpn
0x5005076300c18154
# cat /sys/bus/scsi/devices/0\:0\:1\:0/fcp_lun
0x5719000000000000

# cat /sys/bus/scsi/devices/0\:0\:1\:0/block/dev
8:0
# cat /sys/bus/scsi/devices/0\:0\:1\:0/block/sda1/dev
8:1

# cat /proc/scsi/scsi
Attached devices:
Host: scsi2 Channel: 00 Id: 01 Lun: 00
  Vendor: IBM      Model: 2105F20          Rev: .123
  Type:   Direct-Access                    ANSI SCSI revision: 03

# fdisk /dev/sda

# mke2fs -j /dev/sda1

# mount /dev/sda1 /mnt
# df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/dasda1            2344224   1427948    797196  65% /
none                    511652         0    511652   0% /dev/shm
/dev/dasdb1            2365444     32828   2212456   2% /opt
/dev/sda1              3844088     32828   3615988   1% /mnt

# cd /boot
# mv initrd-2.6.7-1.451.2.3.img initrd-2.6.7-1.451.2.3.img.orig
# mkinitrd -v --with=scsi_mod --with=zfcp --with=sd_mod initrd-2.6.7-1.451.2.3.img 2.6.7-1.451.2.3
Looking for deps of module ide-disk
Looking for deps of module dasd_mod
Looking for deps of module dasd_eckd_mod         dasd_mod
Looking for deps of module dasd_mod
Looking for deps of module dasd_fba_mod  dasd_mod
Looking for deps of module dasd_mod
Looking for deps of module ext3  jbd
Looking for deps of module jbd
Looking for deps of module scsi_mod
Looking for deps of module zfcp  qdio scsi_mod
Looking for deps of module qdio
Looking for deps of module scsi_mod
Looking for deps of module sd_mod        scsi_mod
Looking for deps of module scsi_mod
Using modules:  ./kernel/drivers/s390/block/dasd_mod.ko
./kernel/drivers/s390/block/dasd_eckd_mod.ko
./kernel/drivers/s390/block/dasd_fba_mod.ko ./kernel/fs/jbd/jbd.ko
./kernel/fs/ext3/ext3.ko ./kernel/drivers/scsi/scsi_mod.ko
./kernel/drivers/s390/cio/qdio.ko ./kernel/drivers/s390/scsi/zfcp.ko
./kernel/drivers/scsi/sd_mod.ko
Using loopback device /dev/loop0
/sbin/nash -> /tmp/initrd.cT1534/bin/nash
/sbin/insmod.static -> /tmp/initrd.cT1534/bin/insmod
`/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/s390/block/dasd_mod.ko'-> 
`/tmp/initrd.cT1534/lib/dasd_mod.ko'
`/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/s390/block/dasd_eckd_mod.ko' ->
`/tmp/initrd.cT1534/lib/dasd_eckd_mod.ko'
`/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/s390/block/dasd_fba_mod.ko' ->
`/tmp/initrd.cT1534/lib/dasd_fba_mod.ko'
`/lib/modules/2.6.7-1.451.2.3/./kernel/fs/jbd/jbd.ko' ->
`/tmp/initrd.cT1534/lib/jbd.ko'
`/lib/modules/2.6.7-1.451.2.3/./kernel/fs/ext3/ext3.ko' ->
`/tmp/initrd.cT1534/lib/ext3.ko'
`/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/scsi/scsi_mod.ko' ->
`/tmp/initrd.cT1534/lib/scsi_mod.ko'
`/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/s390/cio/qdio.ko' ->
`/tmp/initrd.cT1534/lib/qdio.ko'
`/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/s390/scsi/zfcp.ko' ->
`/tmp/initrd.cT1534/lib/zfcp.ko'
`/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/scsi/sd_mod.ko' ->
`/tmp/initrd.cT1534/lib/sd_mod.ko'
...
Loading module dasd_mod with options dasd=201,4b2e
Loading module dasd_eckd_mod
Loading module dasd_fba_mod
Loading module jbd
Loading module ext3
Loading module scsi_mod
Loading module qdio
Loading module zfcp
Loading module sd_mod

# zipl -V
Using config file '/etc/zipl.conf'
Target device information
  Device..........................: 5e:00
  Partition.......................: 5e:01
  Device name.....................: dasda
  DASD device number..............: 0201
  Type............................: disk partition
  Disk layout.....................: ECKD/compatible disk layout
  Geometry - heads................: 15
  Geometry - sectors..............: 12
  Geometry - cylinders............: 3308
  Geometry - start................: 24
  File system block size..........: 4096
  Physical block size.............: 4096
  Device size in physical blocks..: 595416
Building bootmap '/boot//bootmap'
Building menu 'rh-automatic-menu'
Adding #1: IPL section 'linux' (default)
  kernel image......: /boot/vmlinuz-2.6.7-1.451.2.3 at 0x10000
  kernel parmline...: 'root=LABEL=/' at 0x1000
  initial ramdisk...: /boot/initrd-2.6.7-1.451.2.3.img at 0x800000
Preparing boot device: dasda (0201).
Preparing boot menu
  Interactive prompt......: disabled
  Menu timeout............: disabled
  Default configuration...: 'linux'
Syncing disks...
Done.

22.3. Using mdadm to Configure RAID-Based and Multipath Storage

Similar to other tools comprising the raidtools package set, the mdadm command can be used to perform all the necessary functions related to administering multiple-device sets. This section explains how mdadm can be used to:
  • Create a RAID device
  • Create a multipath device

22.3.1. Creating a RAID Device With mdadm

To create a RAID device, edit the /etc/mdadm.conf file to define appropriate DEVICE and ARRAY values:
DEVICE /dev/sd[abcd]1
ARRAY /dev/md0 devices=/dev/sda1,/dev/sdb1,/dev/sdc1,/dev/sdd1
In this example, the DEVICE line is using traditional file name globbing (refer to the glob(7) man page for more information) to define the following SCSI devices:
  • /dev/sda1
  • /dev/sdb1
  • /dev/sdc1
  • /dev/sdd1
The ARRAY line defines a RAID device (/dev/md0) that is comprised of the SCSI devices defined by the DEVICE line.
Prior to the creation or usage of any RAID devices, the /proc/mdstat file shows no active RAID devices:
Personalities :
read_ahead not set
Event: 0
unused devices: none
Next, use the above configuration and the mdadm command to create a RAID 0 array:
mdadm -C /dev/md0 --level=raid0 --raid-devices=4 /dev/sda1 /dev/sdb1 /dev/sdc1 \
/dev/sdd1
Continue creating array? yes
mdadm: array /dev/md0 started.
Once created, the RAID device can be queried at any time to provide status information. The following example shows the output from the command mdadm --detail /dev/md0:
/dev/md0:
Version : 00.90.00
Creation Time : Mon Mar  1 13:49:10 2004
Raid Level : raid0
Array Size : 15621632 (14.90 GiB 15.100 GB)
Raid Devices : 4
Total Devices : 4
Preferred Minor : 0
Persistence : Superblock is persistent

Update Time : Mon Mar  1 13:49:10 2004
State : dirty, no-errors
Active Devices : 4
Working Devices : 4
Failed Devices : 0
Spare Devices : 0

Chunk Size : 64K

      Number   Major   Minor   RaidDevice State
         0       8        1        0      active sync   /dev/sda1
         1       8       17        1      active sync   /dev/sdb1
         2       8       33        2      active sync   /dev/sdc1
         3       8       49        3      active sync   /dev/sdd1
           UUID : 25c0f2a1:e882dfc0:c0fe135e:6940d932
         Events : 0.1

22.3.2. Creating a Multipath Device With mdadm

In addition to creating RAID arrays, mdadm can also be used to take advantage of hardware supporting more than one I/O path to individual SCSI LUNs (disk drives). The goal of multipath storage is continued data availability in the event of hardware failure or individual path saturation. Because this configuration contains multiple paths (each acting as an independent virtual controller) accessing a common SCSI LUN (disk drive), the Linux kernel detects each shared drive once "through" each path. In other words, the SCSI LUN (disk drive) known as /dev/sda may also be accessible as /dev/sdb, /dev/sdc, and so on, depending on the specific configuration.
To provide a single device that can remain accessible if an I/O path fails or becomes saturated, mdadm includes an additional parameter to its level option. This parameter multipath directs the md layer in the Linux kernel to re-route I/O requests from one pathway to another in the event of an I/O path failure.
To create a multipath device, edit the /etc/mdadm.conf file to define values for the DEVICE and ARRAY lines that reflect your hardware configuration.

Note

Unlike the previous RAID example (where each device specified in /etc/mdadm.conf must represent different physical disk drives), each device in this file refers to the same shared disk drive.
The command used for the creation of a multipath device is similar to that used to create a RAID device; the difference is the replacement of a RAID level parameter with the multipath parameter:
mdadm -C /dev/md0 --level=multipath --raid-devices=4 /dev/sda1 /dev/sdb1  
 /dev/sdc1 /dev/sdd1
Continue creating array? yes
mdadm: array /dev/md0 started.
Due to the length of the mdadm command line, it has been broken into two lines.
In this example, the hardware consists of one SCSI LUN presented as four separate SCSI devices, each accessing the same storage by a different pathway. Once the multipath device /dev/md0 is created, all I/O operations referencing /dev/md0 are directed to /dev/sda1, /dev/sdb1, /dev/sdc1, or /dev/sdd1 (depending on which path is currently active and operational).
The configuration of /dev/md0 can be examined more closely using the command mdadm --detail /dev/md0 to verify that it is, in fact, a multipath device:
/dev/md0:
Version : 00.90.00
Creation Time : Tue Mar  2 10:56:37 2004
Raid Level : multipath
Array Size : 3905408 (3.72 GiB 3.100 GB)
Raid Devices : 1
Total Devices : 4
Preferred Minor : 0
Persistence : Superblock is persistent

Update Time : Tue Mar  2 10:56:37 2004
State : dirty, no-errors
Active Devices : 1
Working Devices : 4
Failed Devices : 0
Spare Devices : 3

    Number   Major   Minor   RaidDevice State
       0       8       49        0      active sync   /dev/sdd1
       1       8       17        1      spare   /dev/sdb1
       2       8       33        2      spare   /dev/sdc1
       3       8        1        3      spare   /dev/sda1
           UUID : 4b564608:fa01c716:550bd8ff:735d92dc
         Events : 0.1
Another feature of mdadm is the ability to force a device (be it a member of a RAID array or a path in a multipath configuration) to be removed from an operating configuration. In the following example, /dev/sda1 is flagged as being faulty, is then removed, and finally is added back into the configuration. For a multipath configuration, these actions would not affect any I/O activity taking place at the time:
# mdadm /dev/md0 -f /dev/sda1
mdadm: set /dev/sda1 faulty in /dev/md0
# mdadm /dev/md0 -r /dev/sda1
mdadm: hot removed /dev/sda1
# mdadm /dev/md0 -a /dev/sda1
mdadm: hot added /dev/sda1
#

22.4. Configuring IPL from a SCSI Device

Anaconda (the installation program) supports the direct installation to SCSI devices. This section includes information on how to IPL from a SCSI device within z/VM.

22.4.1. IPL the SCSI Disk

To IPL the SCSI disk, we provide the WWPN and LUN to the machine loader using the SET LOADDEV command.
#cp set loaddev portname 50050763 00c18154 lun 57190000 00000000
Ready; T=0.01/0.01 15:47:53
q loaddev
PORTNAME 50050763 00C18154    LUN  57190000 00000000    BOOTPROG 0
BR_LBA   00000000 00000000
Ready; T=0.01/0.01 15:47:56
IPL the SCSI disk using the FCP device defined to the guest.
q fcp
00: FCP  010A ON FCP   010ACHPID C1 SUBCHANNEL = 0000
00:      010A QDIO-ELIGIBLE       QIOASSIST-ELIGIBLE
Ready; T=0.01/0.01 15:51:29

i 010a
00: I 010A
00: HCPLDI2816I Acquiring the machine loader from the processor
controller.
00: HCPLDI2817I Load completed from the processor controller.
00: HCPLDI2817I Now starting machine loader version 0001.
01: HCPGSP2630I The virtual machine is placed in CP mode due to a SIGP
stop and
store status from CPU 00.
00: MLOEVL012I: Machine loader up and running (version 0.13).
00: MLOPDM003I: Machine loader finished, moving data to final storage
location.
Linux version 2.6.7-1.451.2.3 (bhcompile@example.z900.redhat.com) (gcc
version 3.4
.1 20040702 (Red Hat Linux 3.4.1-2)) #1 SMP Wed Jul 14 17:52:22 EDT 2004
We are running under VM (64 bit mode)

Note

The example may vary slightly from your installed system due to the code available during the documentation process for this manual.

22.5. Adding DASD

The following is an example of how to add a DASD volume:

Note

Make sure the device is attached or linked to the Linux system if running under VM.
CP LINK RHEL4X 4B2E 4B2E MR
DASD 4B2E LINKED R/W

Procedure 22.1. Bringing a disk online

  1. Use the cd command to change to the /sys/ directory that represents that volume:
    # cd /sys/bus/ccw/drivers/dasd-eckd/0.0.4b2e/
    # ls -l
    total 0
    -r--r--r--  1 root root 4096 Aug 25 17:04 availability
    -rw-r--r--  1 root root 4096 Aug 25 17:04 cmb_enable
    -r--r--r--  1 root root 4096 Aug 25 17:04 cutype
    -rw-r--r--  1 root root 4096 Aug 25 17:04 detach_state
    -r--r--r--  1 root root 4096 Aug 25 17:04 devtype
    -r--r--r--  1 root root 4096 Aug 25 17:04 discipline
    -rw-r--r--  1 root root 4096 Aug 25 17:04 online
    -rw-r--r--  1 root root 4096 Aug 25 17:04 readonly
    -rw-r--r--  1 root root 4096 Aug 25 17:04 use_diag
  2. Next, check to see if it is already online:
    # cat online
    0
  3. If it is not online, run the following command to bring it online:
    # echo 1 > online
    # cat online
    1
  4. Verify which block devnode it is being accessed as:
    # ls -l
    total 0
    -r--r--r--  1 root root 4096 Aug 25 17:04 availability
    lrwxrwxrwx  1 root root    0 Aug 25 17:07 block -> ../../../../block/dasdb
    -rw-r--r--  1 root root 4096 Aug 25 17:04 cmb_enable
    -r--r--r--  1 root root 4096 Aug 25 17:04 cutype
    -rw-r--r--  1 root root 4096 Aug 25 17:04 detach_state
    -r--r--r--  1 root root 4096 Aug 25 17:04 devtype
    -r--r--r--  1 root root 4096 Aug 25 17:04 discipline
    -rw-r--r--  1 root root    0 Aug 25 17:04 online
    -rw-r--r--  1 root root 4096 Aug 25 17:04 readonly
    -rw-r--r--  1 root root 4096 Aug 25 17:04 use_diag
    As shown in this example, device 4B2E is being accessed as /dev/dasdb.
As an alternative, the recommended method for bringing a disk online (automatically) is to use the following simple command:
# chccwdev -e 4b2e
Once the disk is online, change back to the /root directory and format the device:
# cd
# dasdfmt -b 4096 -d cdl -f /dev/dasdb -l LX4B2E -p -y

cyl    97 of  3338 |#----------------------------------------------|   2%
When the progress bar reaches the end and the format is complete, use fdasd to partition the device:
# fdasd -a /dev/dasdb
auto-creating one partition for the whole disk...
writing volume label...
writing VTOC...
checking !
wrote NATIVE!
rereading partition table...
Next, make a file system on the new partition:
# mke2fs -j /dev/dasdb1
mke2fs 1.35 (28-Feb-2004)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
300960 inodes, 600816 blocks
30040 blocks (5.00%) reserved for the super user
First data block=0
19 block groups
32768 blocks per group, 32768 fragments per group
15840 inodes per group
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376, 294912

Writing inode tables: done
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 39 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.
Mount the new file system:
# mount /dev/dasdb1 /opt
# mount
/dev/dasda1 on / type ext3 (rw)
none on /proc type proc (rw)
none on /sys type sysfs (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
none on /dev/shm type tmpfs (rw)
/dev/dasdb1 on /opt type ext3 (rw)
Add an entry to /etc/fstab so that the file system is mounted at IPL time:
# vi /etc/fstab
# cat /etc/fstab
LABEL=/                 /                       ext3    defaults
1 1
none                    /dev/pts                devpts  gid=5,mode=620
0 0
none                    /dev/shm                tmpfs   defaults
0 0
none                    /proc                   proc    defaults
0 0
none                    /sys                    sysfs   defaults
0 0
/dev/dasdb1             /opt                    ext3    defaults
1 2
Add the device to the option line for the dasd_mod in /etc/modprobe.conf Make sure to add the new device at the end of the list, otherwise it changes the device number : devnode mapping and file systems are not on the devices they used to be on.
# vi /etc/modprobe.conf
# cat /etc/modprobe.conf
alias eth0 qeth
options dasd_mod dasd=201,4B2E
Rerun mkinitrd to pick up the changes to modprobe.conf so that the device can be online and mountable after the next IPL:
Note that the example below has been modified slightly for readability and for printing purposes. Each line that ends with "(elf64-s390)" should be treated as one line with no spaces, such as /tmp/initrd.AR1182/lib/dasd_mod.ko(elf64-s390).
# cd /boot
# mv initrd-2.6.7-1.451.2.3.img initrd-2.6.7-1.451.2.3.img.old
# mkinitrd -v initrd-2.6.7-1.451.2.3.img 2.6.7-1.451.2.3
Looking for deps of module ide-disk
Looking for deps of module dasd_mod
Looking for deps of module dasd_eckd_mod         dasd_mod
Looking for deps of module dasd_mod
Looking for deps of module dasd_fba_mod  dasd_mod
Looking for deps of module dasd_mod
Looking for deps of module ext3  jbd
Looking for deps of module jbd
Using modules:  ./kernel/drivers/s390/block/dasd_mod.ko
./kernel/drivers/s390/block/dasd_eckd_mod.ko
./kernel/drivers/s390/block/dasd_fba_mod.ko ./kernel/fs/jbd/jbd.ko
./kernel/fs/ext3/ext3.ko
Using loopback device /dev/loop0
/sbin/nash -> /tmp/initrd.AR1182/bin/nash
/sbin/insmod.static -> /tmp/initrd.AR1182/bin/insmod
copy from
/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/s390/block/dasd_mod.ko
(elf64-s390) to 
/tmp/initrd.AR1182/lib/dasd_mod.ko(elf64-s390)
copy from
/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/s390/block/dasd_eckd_mod.ko
(elf64-s390) to 
/tmp/initrd.AR1182/lib/dasd_eckd_mod.ko
(elf64-s390)
copy from
/lib/modules/2.6.7-1.451.2.3/./kernel/drivers/s390/block/dasd_fba_mod.ko
(elf64-s390) to 
/tmp/initrd.AR1182/lib/dasd_fba_mod.ko
(elf64-s390)
copy from
/lib/modules/2.6.7-1.451.2.3/./kernel/fs/jbd/jbd.ko(elf64-s390) to 
/tmp/initrd.AR1182/lib/jbd.ko(elf64-s390)
copy from
/lib/modules/2.6.7-1.451.2.3/./kernel/fs/ext3/ext3.ko(elf64-s390) to 
/tmp/initrd.AR1182/lib/ext3.ko(elf64-s390)
Loading module dasd_mod with options dasd=201,4B2E
Loading module dasd_eckd_mod
Loading module dasd_fba_mod
Loading module jbd
Loading module ext3
Run zipl to save the changes to initrd for the next IPL:
# zipl -V
Using config file '/etc/zipl.conf'
Target device information
  Device..........................: 5e:00
  Partition.......................: 5e:01
  Device name.....................: dasda
  DASD device number..............: 0201
  Type............................: disk partition
  Disk layout.....................: ECKD/compatible disk layout
  Geometry - heads................: 15
  Geometry - sectors..............: 12
  Geometry - cylinders............: 3308
  Geometry - start................: 24
  File system block size..........: 4096
  Physical block size.............: 4096
  Device size in physical blocks..: 595416
Building bootmap '/boot//bootmap'
Building menu 'rh-automatic-menu'
Adding #1: IPL section 'linux' (default)
  kernel image......: /boot/vmlinuz-2.6.7-1.451.2.3 at 0x10000
  kernel parmline...: 'root=LABEL=/' at 0x1000
  initial ramdisk...: /boot/initrd-2.6.7-1.451.2.3.img at 0x800000
Preparing boot device: dasda (0201).
Preparing boot menu
  Interactive prompt......: disabled
  Menu timeout............: disabled
  Default configuration...: 'linux'
Syncing disks...
Done.

22.6. Adding a Network Device

The process of adding a network device has changed with the migration of the 2.4 kernel to the 2.6 kernel:
  • The proc file system is no longer used to control or obtain status on network devices.
  • The new sys file system now provides facilities for controlling devices.
  • /sys/class/net/interface_name/device now provides status on active devices.
    interface_name is a name such as eth0 or eth2 that is given to a network interface by the device driver when the device is configured.
  • /etc/chandev.conf no longer exists.
    The sys file system now contains the information that was placed in /etc/chandev.conf.
  • /etc/modules.conf no longer exists.
    Network interface alias specifications are now placed in /etc/modprobe.conf.
Section 22.6.1, “Adding a qeth Device” describes in detail how to add a qeth device to an existing instance of Red Hat Enterprise Linux. Section 22.6.2, “Quick Reference for Adding Network Devices” is a quick reference for installing other IBM System z network interfaces.

22.6.1. Adding a qeth Device

First, determine whether the qeth device driver modules are loaded.
# lsmod | grep qeth
qeth                  135240  0
qdio                   45360  2 qeth
ipv6                  303984  13 qeth
ccwgroup               15104  1 qeth
If the output of the lsmod command shows that the modules are not loaded, you must run the modprobe command to load them:
# modprobe qeth
Next, create a qeth group device.
# echo read_device_bus_id,write_device_bus_id,
data_device_bus_id > /sys/bus/ccwgroup/drivers/qeth/group
Due to the length of this command, it has been broken into two lines.
In the following example, read_device_bus_id is 0.0.0600, write_device_bus_id is 0.0.0601, and data_device_bus_id is 0.0.0602. The device is a z/VM virtual NIC and the IP address to be assigned to this interface is 192.168.70.69.
# echo 0.0.0600,0.0.0601,0.0.0602 > /sys/bus/ccwgroup/drivers/qeth/group
Next, verify that the qeth group device was created properly:
# ls /sys/bus/ccwgroup/drivers/qeth
0.0.0600  0.0.09a0  group  notifier_register
You may optionally add a portname. First, you must check to see if a portname is required:
# cat /sys/bus/ccwgroup/drivers/qeth/0.0.0600/portname
no portname required
The response indicates that you do not need to provide a portname.
To add a port name, check that the devices are offline, and then run the following command:

Note

The device(s) must be offline when you add a portname.
# echo portname > /sys/bus/ccwgroup/drivers/qeth/0.0.0600/portname
Next, bring the device back online:
# echo 1 > /sys/bus/ccwgroup/drivers/qeth/0.0.0600/online
Then verify the state of the device:
# cat /sys/bus/ccwgroup/drivers/qeth/0.0.0600/online
1
A return value of "1" indicates that the device is online, while a return value '0' indicates that the device is offline.
Check to see what interface name was assigned to the device:
# cat /sys/bus/ccwgroup/drivers/qeth/0.0.0600/if_name
eth1
You may optionally set additional parameters and features, depending on the way you are setting up your system and the features you require.
  • add_hhlen
  • broadcast_mode
  • buffer_count
  • canonical_macaddr
  • checksumming
  • detach_state
  • fake_broadcast
  • fake_ll
  • ipa_takeover
  • portno
  • priority_queueing
  • recover
  • route4
  • rxip
  • ungroup
  • vipa
For information on how these features work, refer to http://www-05.ibm.com/e-business/linkweb/publications/servlet/pbi.wss?CTY=US&FNC=SRX&PBL=SC33-8289-02 (Device Drivers, Features, and Commands - SC33-8289-02).
Now you need to create the configuration file for your new interface. The network interface configuration files are placed in /etc/sysconfig/network-scripts/.
The network configuration files use the naming convention ifcfg-device, where device is the value found in the if_name file in the qeth group device that was created earlier. In this example it is eth1.
If there is an existing configuration file for another device of the same type already defined, the simplest solution is to copy it to the new name.
# cd /etc/sysconfig/network-scripts
# cp ifcfg-eth0 ifcfg-eth1
If you do not have a similar device defined you must create one. Use this example of ifcfg-eth0 as a template.
/etc/sysconfig/network-scripts/ifcfg-eth0
# IBM QETH
DEVICE=eth0
BOOTPROTO=static
HWADDR=00:06:29:FB:5F:F1
IPADDR=9.12.20.136
NETMASK=255.255.255.0
ONBOOT=yes
NETTYPE=qeth
SUBCHANNELS=0.0.09a0,0.0.09a1,0.0.09a2
TYPE=Ethernet
Edit the new ifcfg-eth1 file.
Remove the HWADDR line for now.
Modify the DEVICE statement to reflect the contents of the if_name file from your ccwgroup.
Modify the IPADDR statement to reflect the IP address of your new interface.
Modify the NETMASK statement as needed.
If you want your new interface to be activated at boot time, then make sure ONBOOT is set to yes .
Make sure the SUBCHANNELS statement matches the hardware addresses for your qeth device.
/etc/sysconfig/network-scripts/ifcfg-eth1
# IBM QETH
DEVICE=eth1
BOOTPROTO=static
IPADDR=192.168.70.87
NETMASK=255.255.255.0
ONBOOT=yes
NETTYPE=qeth
SUBCHANNELS=0.0.0600,0.0.0601,0.0.0602
TYPE=Ethernet
A qeth device requires an alias definition in /etc/modprobe.conf. Edit this file and add an alias for your interface.
/etc/modprobe.conf
alias eth0 qeth
alias eth1 qeth
options dasd_mod dasd=0.0.0100,0.0.4b19
Now you can start the new interface:
# ifup eth1
Check the status of the interface:
# ifconfig eth1
eth1      Link encap:Ethernet  HWaddr 02:00:00:00:00:01
          inet addr:192.168.70.87  Bcast:192.168.70.255  Mask:255.255.255.0
          inet6 addr: fe80::ff:fe00:1/64 Scope:Link
          UP BROADCAST RUNNING NOARP MULTICAST  MTU:1492  Metric:1
          RX packets:23 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:644 (644.0 b)  TX bytes:264 (264.0 b)
Note that the HWaddr field in the first line of the ifconfig command output. The value after that must be added to the ifcfg-eth1 file. Add a line like the following to that file:
HWADDR=02:00:00:00:00:01
Now ifcfg-eth1 looks similar to the following:
# IBM QETH
DEVICE=eth1
HWADDR=02:00:00:00:00:01
BOOTPROTO=static
IPADDR=192.168.70.69
NETMASK=255.255.255.0
ONBOOT=yes
NETTYPE=qeth
SUBCHANNELS=0.0.0600,0.0.0601,0.0.0602
TYPE=Ethernet
Check the routing for the new interface:
# route
Kernel IP routing table
Destination     Gateway         Genmask        Flags Metric Ref  Use Iface
192.168.70.0    *               255.255.255.0  U     0      0      0 eth1
9.12.20.0       *               255.255.255.0  U     0      0      0 eth0
169.254.0.0     *               255.255.0.0    U     0      0      0 eth1
default         pdlrouter-if5.p 0.0.0.0        UG    0      0      0 eth0
Verify your changes by using the ping command to ping the gateway:
# ping -c 1 192.168.70.8
PING 192.168.70.8 (192.168.70.8) 56(84) bytes of data.
64 bytes from 192.168.70.8: icmp_seq=0 ttl=63 time=8.07 ms
If the default route information has changed, you must also update /etc/sysconfig/network accordingly.

22.6.2. Quick Reference for Adding Network Devices

There are several basic tasks for adding a network interface on IBM System z.
  • Load the device driver.
  • Create the group device.
  • Configure the device.
  • Set the device online.
  • Define the alias (if needed).
  • Create a configuration script.
  • Activate the device.
The following sections provide basic information for each task of each IBM System z network device driver.

22.6.2.1. Working With the LCS Device Driver

The LAN channel station (LCS) device driver supports OSA-2 Ethernet/Token Ring, OSA-Express Fast Ethernet in non-QDIO mode, and OSA-Express High Speed Token Ring in non-QDIO mode. For z990, the LCS driver also supports Gigabit Ethernet in non-QDIO mode (including 1000Base-T).
Based on the type of interface being added, the LCS driver assigns one of two base interface names: ethn for OSA-Express Fast Ethernet and Gigabit Ethernet trn for Token Ring, where n is an integer that uniquely identifies the device. n is 0 for the first device of that type, 1 for the second, and so on.
  • Load the device driver:
    # modprobe lcs
  • Create the group device:
    # echo read_device_bus_id,write_device_bus_id >
    		/sys/bus/ccwgroup/drivers/lcs/group
    Due to the length of this command, it has been broken into two lines.
  • Configure the device.
    OSA cards can provide up to 16 ports for a single CHPID. By default, the LCS group device uses port 0. To use a different port, issue a command similar to the following:
    # echo portno > /sys/bus/ccwgroup/drivers/lcs/device_bus_id/portno
    For more information about configuration of the LCS driver, refer to the following:
    http://www-05.ibm.com/e-business/linkweb/publications/servlet/pbi.wss?CTY=US&FNC=SRX&PBL=SC33-8289-02 (Linux for IBM System z and S/390 Device Drivers, Features, and Commands)
  • Set the device online:
    # echo 1 > /sys/bus/ccwgroup/drivers/lcs/read_device_bus_id/online
  • Define the alias.
    Based on the type interface being added, add a line to /etc/modprobe.conf that is similar to one of the following:
    ethn alias lcs
    trn alias lcs
  • Create a configuration script.
    Create a file in /etc/sysconfig/network-scripts/ with a name like one of the following:
    ifcfg-ethn
    ifcfg-trn
    The file should look similar to the following:
    /etc/sysconfig/network-scripts/ifcfg-eth0
    # IBM LCS
    DEVICE=eth0
    BOOTPROTO=static
    HWADDR=00:06:29:FB:5F:F1
    IPADDR=9.12.20.136
    NETMASK=255.255.255.0
    ONBOOT=yes
    NETTYPE=lcs
    SUBCHANNELS=0.0.09a0,0.0.09a1
    PORTNAME=0
    TYPE=Ethernet
    Based on the type interface being added, the DEVICE parameter should be one of the following:
    DEVICE=ethn
    DEVICE=trn
  • Activate the device.
    Based on the type interface being added, issue an ifup command:
    # ifup ethn
    # ifup trn

22.6.2.2. Working With the QETH Device Driver

The QETH network device driver supports IBM System z HiperSockets, OSA-Express Fast Ethernet, Gigabit Ethernet (including 1000Base-T), High Speed Token Ring, and ATM features (running Ethernet LAN emulation) in QDIO mode.
Based on the type of interface being added, the QETH driver assigns one of three base interface names:
  • hsin for HiperSocket devices
  • ethn for OSA-Express Fast Ethernet and Gigabit Ethernet
  • trn for Token Ring
The value n is an integer that uniquely identifies the device. n is 0 for the first device of that type, 1 for the second, and so on.
  • Load the device driver:
    # modprobe qeth
  • Create the group device:
    # echo read_device_bus_id,write_device_bus_id,data_device_bus_id >
    /sys/bus/ccwgroup/drivers/qeth/group
    Due to the length of this command, it has been broken into two lines.
  • Configure the device.
    For more information about configuration of the QETH driver, refer to the following:
    http://oss.software.ibm.com/developerworks/opensource/linux390/docu/lx26apr04dd01.pdf (Linux for IBM System z and S/390 Device Drivers, Features, and Commands)
  • Set the device online:
    # echo 1 > /sys/bus/ccwgroup/drivers/qeth/read_device_bus_id/online
  • Define the alias.
    Based on the type interface being added, add a line to /etc/modprobe.conf that is like one of the following:
    hsin alias qeth
    ethn alias qeth
    trn alias qeth
  • Create a configuration script.
    Create a file in /etc/sysconfig/network-scripts/ with a name like one of the following:
    ifcfg-hsin 
    ifcfg-ethn
    ifcfg-trn
    The file should look like this:
    /etc/sysconfig/network-scripts/ifcfg-eth0
    # IBM QETH
    DEVICE=eth0
    BOOTPROTO=static
    HWADDR=00:06:29:FB:5F:F1
    IPADDR=9.12.20.136
    NETMASK=255.255.255.0
    ONBOOT=yes
    NETTYPE=qeth
    SUBCHANNELS=0.0.09a0,0.0.09a1,0.0.09a2
    TYPE=Ethernet
    Based on the type interface being added, the DEVICE parameter should be like one of the following:
    DEVICE=hsin
    DEVICE=ethn
    DEVICE=trn
  • Activate the device.
    Based on the type interface being added, issue an ifup command:
    # ifup hsin
    # ifup ethn
    # ifup trn

22.7. Kernel-Related Information

Red Hat Enterprise Linux includes a modification to the way the Linux kernel timer interrupt is handled. Normally, a hardware timer is set to generate periodic interrupts at a fixed rate (100 times a second for most architectures). These periodic timer interrupts are used by the kernel to schedule various internal housekeeping tasks, such as process scheduling, accounting, and maintaining system uptime.
While a timer-based approach works well for a system environment where only one copy of the kernel is running, it can cause additional overhead when many copies of the kernel are running on a single system (for example, as z/VM(R) guests). In these cases, having thousands of copies of the kernel each generating interrupts many times a second can result in excessive system overhead.
Therefore, Red Hat Enterprise Linux now includes the ability to turn off periodic timer interrupts. This is done through the /proc/ file system. To disable periodic timer interrupts, issue the following command:
 echo 0 > /proc/sys/kernel/hz_timer
To enable periodic timer interrupts, issue the following command:
 echo 1 > /proc/sys/kernel/hz_timer
By default, periodic timer interrupts are disabled.
Periodic timer interrupt states can also be set at boot-time; to do so, add the following line to /etc/sysctl.conf to disable periodic timer interrupts:
 kernel.hz_timer = 0

Note

Disabling periodic timer interrupts can violate basic assumptions in system accounting tools. If you notice a malfunction related to system accounting, verify that the malfunction disappears if periodic timer interrupts are enabled, then submit a bug at http://bugzilla.redhat.com/bugzilla/ (for malfunctioning bundled tools), or inform the tool vendor (for malfunctioning third-party tools).

Part IV. Common Tasks

Information that is common to all architectures related to registering your system with Red Hat Network, choosing whether to install or upgrade, and information on disk partitioning is contained in this section.

Chapter 23. Updating Your System

23.1. Driver update rpm packages

Occasionally, when a new piece of hardware is not yet supported in the kernel that you have installed, Red Hat or a hardware vendor might make a driver update available. Although you can install driver updates during the installation process (refer to Chapter 7, Updating drivers during installation on Intel and AMD systems for Intel and AMD systems and Chapter 13, Updating drivers during installation on IBM POWER systems for IBM POWER systems) we recommend that you do this only for devices that are essential to carry out the installation. In all other cases, complete the installation first, and then add support for the device with a driver update rpm package as described in this section.
Do not install a driver update rpm unless you are certain that your system requires it. Installing a driver update on a system for which it was not intended can cause system difficulties.
To see a list of driver updates already installed on your system, click Applications > Add/Remove Software on your desktop, and enter the root password if prompted for it. Click the Search tab, enter the word kmod- (notice the final -) and click Search.
Listing installed Driver Update RPM packages

Figure 23.1. Listing installed Driver Update RPM packages

Alternatively, you can use the command line, as follows:
$ rpm -­qa | egrep ^kmod-
Note the - on the end of kmod. This will list all installed packages that begin with kmod-, which should include all driver updates that are currently installed on your system. Additional drivers provided by third-party update software are not listed in this output. Contact the third-party vendor for details.
To install a new driver update rpm package:
  1. Download the driver update rpm package from the location specified by Red Hat or your hardware vendor. The package file name will begin with kmod (short for kernel module) and have a form similar to this example:
    kmod-­ipw3945-­1.2.0­4.17.el5.i686.rpm
    In the example, the driver update rpm package supplies an Intel IPW3945 WiFi driver update with version number 1.2.0-4.17 for Red Hat Enterprise Linux 5, on i686 systems. A version of this driver package for systems running a Xen kernel will be similar, but include xen in the package name:
    kmod-­ipw3945-­xen-­1.2.0­4.17.el5.i686.rpm
    Driver update rpm packages are signed packages, and like all other software packages, they are automatically validated at install time. To perform this step manually, type the following at a command line:
    $ rpm --­­checksig -­v filename.rpm
    where filename.rpm is the driver update rpm package file name. This verifies the package against using the standard Red Hat GPG package signing key that is already installed on any Red Hat Enterprise Linux 5.11 system. If you need this key for verification purposes on another system, you can can obtain it from: https://www.redhat.com/security/team/key/
  2. Locate and double-click the file that you downloaded. The system might prompt you for the root password, after which it will present the following Installing Packages box:
    The installing packages box

    Figure 23.2. The installing packages box

    Click Apply to complete the package installation.
    Alternatively, you can install a driver update manually on the command line:
    $ rpm -­ivh kmod-­ipw3945-­1.2.0­4.17.el5.i686
    
  3. Whether you used a graphical install, or a command line install, reboot your system to ensure your system is using the new driver.
If Red Hat ships a kernel errata update before the next release of Red Hat Enterprise Linux, your system will continue to use the driver updates that you have installed. There is no need to re-install driver updates following an errata update. Generally, when Red Hat releases a new version of Red Hat Enterprise Linux, all driver updates for the previous version are incorporated in the new version. However, if it was not possible to include a particular driver, you will need to perform another driver update when you install the new version of Red Hat Enterprise Linux. In this case, Red Hat or your hardware party vendor will inform you of the location of the update.

Chapter 24. Upgrading Your Current System

This chapter explains the various methods available for upgrading your Red Hat Enterprise Linux system.

24.1. Determining Whether to Upgrade or Re-Install

Important

Although anaconda provides an option for upgrading from earlier major versions of Red Hat Enterprise Linux to Red Hat Enterprise Linux 5.11, Red Hat does not currently support this. More generally, Red Hat does not support in-place upgrades between any major versions of Red Hat Enterprise Linux. (A major version is denoted by a whole number version change. For example, Red Hat Enterprise Linux 4 and Red Hat Enterprise Linux 5 are both major versions of Red Hat Enterprise Linux.)
In-place upgrades across major releases do not preserve all system settings, services or custom configurations. Consequently, Red Hat strongly recommends fresh installations when upgrading from one major version to another.
While upgrading from Red Hat Enterprise Linux version 4 Update 4 is technically possible, you are more likely to have a consistent experience by backing up your data and then installing this release of Red Hat Enterprise Linux 5.11 over your previous Red Hat Enterprise Linux installation.
To upgrade from Red Hat Enterprise Linux 4 you should bring your system up to date using RHN before performing the upgrade.
This recommended reinstallation method helps to ensure the best system stability possible.
For more information about re-installing your Red Hat Enterprise Linux system, refer to the Whitepapers available online at http://www.redhat.com/rhel/resource_center/.
If you currently use Red Hat Enterprise Linux 4 Update 4, you can perform a traditional, installation program-based upgrade.
However, before you choose to upgrade your system, there are a few things you should keep in mind:
  • Individual package configuration files may or may not work after performing an upgrade due to changes in various configuration file formats or layouts.
  • Third party or ISV applications may not work correctly following the upgrade.
  • If you have one of Red Hat's layered products (such as the Cluster Suite) installed, it may need to be manually upgraded after the Red Hat Enterprise Linux upgrade has been completed.
  • If you have package repositories from providers other than Red Hat enabled, note that software installed from those repositories may not function properly after a system upgrade. Red Hat cannot guarantee that such repositories are up-to-date.
Upgrading your system installs updated versions of the packages which are currently installed on your system.
The upgrade process preserves existing configuration files by renaming them with an .rpmsave extension (for example, sendmail.cf.rpmsave). The upgrade process also creates a log of its actions in /root/upgrade.log.

Warning

As software evolves, configuration file formats can change. It is very important to carefully compare your original configuration files to the new files before integrating your changes.

Note

It is always a good idea to back up any data that you have on your systems. For example, if you are upgrading or creating a dual-boot system, you should back up any data you wish to keep on your hard drive(s). Mistakes do happen and can result in the loss of all of your data.
Some upgraded packages may require the installation of other packages for proper operation. If you choose to customize your packages to upgrade, you may be required to resolve dependency problems. Otherwise, the upgrade procedure takes care of these dependencies, but it may need to install additional packages which are not on your system.
Depending on how you have partitioned your system, the upgrade program may prompt you to add an additional swap file. If the upgrade program does not detect a swap file that equals twice your RAM, it asks you if you would like to add a new swap file. If your system does not have a lot of RAM (less than 256 MB), it is recommended that you add this swap file.

24.2. Upgrading Your System

The Upgrade Examine screen appears if you have instructed the installation program to perform an upgrade.

Note

If the contents of your /etc/redhat-release file have been changed from the default, your Red Hat Enterprise Linux installation may not be found when attempting an upgrade to Red Hat Enterprise Linux 5.11.
You can relax some of the checks against this file by booting with the following boot command:
linux upgradeany
Use the linux upgradeany command if your Red Hat Enterprise Linux installation was not given as an option to upgrade.
To perform an upgrade, select Perform an upgrade of an existing installation. Click Next when you are ready to begin your upgrade.
To re-install your system, select Perform a new Red Hat Enterprise Linux installation and refer to http://www.redhat.com/docs/wp/ as well as Chapter 4, Installing on Intel® and AMD Systems, Chapter 12, Installing on IBM System i and IBM System p systems, or Chapter 17, Installing on IBM System z Systems for further instructions.
To perform a new installation of Red Hat Enterprise Linux on your system, select Perform a new Red Hat Enterprise Linux installation and refer to Chapter 4, Installing on Intel® and AMD Systems, Chapter 12, Installing on IBM System i and IBM System p systems, or Chapter 17, Installing on IBM System z Systems for further instructions.

Chapter 25. Register Your System and Apply Subscriptions

25.1. Registering the System

Before you can access service and software maintenance information and enhanced support included as part of your subscription, you must register your new system with Red Hat and associate or attach the appropriate subscriptions with your system.
A Red Hat subscription supplied your system access to:
  • Software updates, errata, and maintenance
  • Red Hat technical support resources and Knowledgebase articles
The Red Hat Subscription Management ⁠Subscription Concepts and Workflows has information on different environments and workflows. The basic registration process (which is described in this section) registers a system with Customer Portal Subscription Management (Red Hat's hosted services) and automatically subscribes the system to the best-matched subscriptions. It is also possible to register a system with a Subscription Asset Manager subscription service, CloudForms System Engine, or to register a disconnected system through the Customer Portal.

25.1.1. Registering at Firstboot

The first time you boot a new Red Hat Enterprise Linux system, the firstboot system prompts you to register the system and auto-attach the matching subscriptions.
Red Hat uses X.509 certificates to identify installed products on a system, the subscriptions attached to a system, and the system itself within the subscription service inventory. There are several different subscription services which use and recognize certificate-based subscriptions, and a system can be registered with any of them in firstboot:
  • Customer Portal Subscription Management, hosted services from Red Hat (the default)
  • Subscription Asset Manager, an on-premise subscription server which proxies content delivery back to the Customer Portal's services
  • CloudForms System Engine, an on-premise service which handles both subscription services and content delivery
The specific type of subscription/content service does not need to be selected; all three server types (Customer Portal Subscription Management, Subscription Asset Manager, and CloudForms System Engine) are within Red Hat Subscription Management and use the same types of service APIs. The only thing that needs to be identified is the hostname of the service to connect to and then the appropriate user credentials for that service.
  1. To identify which subscription server to use for registration, enter the hostname of the service. The default service is Customer Portal Subscription Management, with the hostname subscription.rhn.redhat.com. To use a different subscription service, such as Subscription Asset Manager, enter the hostname of the local server.
  2. Click Forward.
  3. Enter the user credentials for the given subscription service to log in.

    Important

    The user credentials to use depend on the subscription service. When registering with the Customer Portal, use the Red Hat Network credentials for the administrator or company account.
    However, for Subscription Asset Manager or CloudForms System engine, the user account to use is created within the on-premise service and probably is not the same as the Customer Portal user account.
    If you have lost your login or password for the Customer Portal, recover them from https://www.redhat.com/wapps/sso/rhn/lostPassword.html. For lost login or password information for Subscription Asset Manager or CloudForms System Engine, contact your local administrator.
  4. Set the system name for the host. This is anything which uniquely and clearly identifies the system within the subscription service inventory. This is usually the hostname or fully-qualified domain name of the machine, but it can be any string.
  5. Optional. Set whether subscriptions should be set manually after registration. By default, this checkbox is unchecked so that the best-matched subscriptions are automatically applied to the system. Selecting this checkbox means that subscriptions must be added to the system manually after firstboot registration is complete. (Even if subscriptions are auto-attached, additional subscriptions can be added to the system later using the local Subscription Manager tools.)
  6. When registration begins, firstboot scans for organizations and environments (sub-domains within the organization) to which to register the system.
    IT environments that use Customer Portal Subscription Management have only a single organization, so no further configuration is necessary. IT infrastructures that use a local subscription service like Subscription Asset Manager might have multiple organizations configured, and those organizations may have multiple environments configured within them.
    If multiple organizations are detected, Subscription Manager prompts to select the one to join.
  7. If you decided to let Subscription Manager automatically attach subscriptions to the system (the default), then the system scans for the subscriptions to attach as part of the registration process.
    When registration is complete, the Subscription Manager reports the applied service level for the system based on the information in the selected subscription and the specific subscription that has been attached to the new system. This subscription selection must be confirmed to complete the registration process.
    If you selected to apply subscriptions later, then that part of the registration process is skipped, and the Subscription Manager screen in firstboot simply instructs you to attach subscriptions later.
  8. Click Forward to move to the next configuration area for firstboot, user setup.

25.1.2. Registering After Firstboot

The system can be registered using the local Red Hat Subscription Manager tools.

Note

Red Hat Subscription Manager (GUI and CLI) must be run as root.
To register from the command line, use the register command with the --autosubscribe option so that the best-matched subscriptions are automatically attached. For example:
[root@server ~]# subscription-manager register --autosubscribe
Username: admin@example.com
Password:

The system has been registered with id: 30a3dc1b-db07-4ee7-bfb0-e09504b4033c
Installed Product Current Status:
Product Name:           Red Hat Enterprise Linux Server
Status:                 Subscribed
To register using the Red Hat Subscription Manager GUI:
  1. Launch Subscription Manager. For example:
    [root@server ~]# subscription-manager-gui
  2. In the System menu of the Subscription Manager window, select the Register item.
  3. Enter the hostname of the subscription server to which to register the system. This server, by default, is Customer Portal Subscription Management (the hosted service), at subscription.rhn.redhat.com. To register with a Subscription Asset Manager server or a CloudForms System Engine server, enter the appropriate hostname.
  4. Enter the username and password of the user account on the subscription service.

    Important

    The user credentials to use depend on the subscription service. When registering with the Customer Portal, use the Red Hat Network credentials for the administrator or company account.
    However, for Subscription Asset Manager or CloudForms System engine, the user account to use is created within the on-premise service and probably is not the same as the Customer Portal user account.
  5. Optionally, select the Skip automatic subscription selection... checkbox.
    By default, the registration process automatically subscribes the system to the best matched subscription. This can be turned off so that the subscriptions can be selected manually.

25.1.3. Unregistering the System

The system is unregistered from a Red Hat Subscription Management service — Customer Portal Subscription Management, Subscription Asset Manager, or CloudForms System Engine using the Red Hat Subscription Manager tools.
For example, from the command line, use the unregister command:
[root@server1 ~]# subscription-manager unregister
From the Subscription Manager UI:
  1. Launch Subscription Manager. For example:
    [root@server ~]# subscription-manager-gui
  2. In the System menu of the Subscription Manager window, select the Unregister item.

Chapter 26. An Introduction to Disk Partitions

Note

This appendix is not necessarily applicable to non-x86-based architectures. However, the general concepts mentioned here may apply.
This appendix is not necessarily applicable to non-x86-based architectures. However, the general concepts mentioned here may apply.
If you are reasonably comfortable with disk partitions, you could skip ahead to Section 26.1.4, “Making Room For Red Hat Enterprise Linux”, for more information on the process of freeing up disk space to prepare for a Red Hat Enterprise Linux installation. This section also discusses the partition naming scheme used by Linux systems, sharing disk space with other operating systems, and related topics.

26.1. Hard Disk Basic Concepts

Hard disks perform a very simple function — they store data and reliably retrieve it on command.
When discussing issues such as disk partitioning, it is important to know a bit about the underlying hardware. Unfortunately, it is easy to become bogged down in details. Therefore, this appendix uses a simplified diagram of a disk drive to help explain what is really happening when a disk drive is partitioned. Figure 26.1, “An Unused Disk Drive”, shows a brand-new, unused disk drive.
An Unused Disk Drive

Figure 26.1. An Unused Disk Drive

Not much to look at, is it? But if we are talking about disk drives on a basic level, it is adequate. Say that we would like to store some data on this drive. As things stand now, it will not work. There is something we need to do first.

26.1.1. It is Not What You Write, it is How You Write It

Experienced computer users probably got this one on the first try. We need to format the drive. Formatting (usually known as "making a file system") writes information to the drive, creating order out of the empty space in an unformatted drive.
Disk Drive with a File System

Figure 26.2. Disk Drive with a File System

As Figure 26.2, “Disk Drive with a File System”, implies, the order imposed by a file system involves some trade-offs:
  • A small percentage of the drive's available space is used to store file system-related data and can be considered as overhead.
  • A file system splits the remaining space into small, consistently-sized segments. For Linux, these segments are known as blocks. [11]
Given that file systems make things like directories and files possible, these trade-offs are usually seen as a small price to pay.
It is also worth noting that there is no single, universal file system. As Figure 26.3, “Disk Drive with a Different File System”, shows, a disk drive may have one of many different file systems written on it. As you might guess, different file systems tend to be incompatible; that is, an operating system that supports one file system (or a handful of related file system types) may not support another. This last statement is not a hard-and-fast rule, however. For example, Red Hat Enterprise Linux supports a wide variety of file systems (including many commonly used by other operating systems), making data interchange between different file systems easy.
Disk Drive with a Different File System

Figure 26.3. Disk Drive with a Different File System

Of course, writing a file system to disk is only the beginning. The goal of this process is to actually store and retrieve data. Let us take a look at our drive after some files have been written to it.
Disk Drive with Data Written to It

Figure 26.4. Disk Drive with Data Written to It

As Figure 26.4, “Disk Drive with Data Written to It”, shows, some of the previously-empty blocks are now holding data. However, by just looking at this picture, we cannot determine exactly how many files reside on this drive. There may only be one file or many, as all files use at least one block and some files use multiple blocks. Another important point to note is that the used blocks do not have to form a contiguous region; used and unused blocks may be interspersed. This is known as fragmentation. Fragmentation can play a part when attempting to resize an existing partition.
As with most computer-related technologies, disk drives changed over time after their introduction. In particular, they got bigger. Not larger in physical size, but bigger in their capacity to store information. And, this additional capacity drove a fundamental change in the way disk drives were used.

26.1.2. Partitions: Turning One Drive Into Many

As disk drive capacities soared, some people began to wonder if having all of that formatted space in one big chunk was such a great idea. This line of thinking was driven by several issues, some philosophical, some technical. On the philosophical side, above a certain size, it seemed that the additional space provided by a larger drive created more clutter. On the technical side, some file systems were never designed to support anything above a certain capacity. Or the file systems could support larger drives with a greater capacity, but the overhead imposed by the file system to track files became excessive.
The solution to this problem was to divide disks into partitions. Each partition can be accessed as if it was a separate disk. This is done through the addition of a partition table.

Note

While the diagrams in this chapter show the partition table as being separate from the actual disk drive, this is not entirely accurate. In reality, the partition table is stored at the very start of the disk, before any file system or user data. But for clarity, they are separate in our diagrams.
Disk Drive with Partition Table

Figure 26.5. Disk Drive with Partition Table

As Figure 26.5, “Disk Drive with Partition Table” shows, the partition table is divided into four sections or four primary partitions. A primary partition is a partition on a hard drive that can contain only one logical drive (or section). Each section can hold the information necessary to define a single partition, meaning that the partition table can define no more than four partitions.
Each partition table entry contains several important characteristics of the partition:
  • The points on the disk where the partition starts and ends
  • Whether the partition is "active"
  • The partition's type
Let us take a closer look at each of these characteristics. The starting and ending points actually define the partition's size and location on the disk. The "active" flag is used by some operating systems' boot loaders. In other words, the operating system in the partition that is marked "active" is booted.
The partition's type can be a bit confusing. The type is a number that identifies the partition's anticipated usage. If that statement sounds a bit vague, that is because the meaning of the partition type is a bit vague. Some operating systems use the partition type to denote a specific file system type, to flag the partition as being associated with a particular operating system, to indicate that the partition contains a bootable operating system, or some combination of the three.
By this point, you might be wondering how all this additional complexity is normally used. Refer to Figure 26.6, “Disk Drive With Single Partition”, for an example.
Disk Drive With Single Partition

Figure 26.6. Disk Drive With Single Partition

In many cases, there is only a single partition spanning the entire disk, essentially duplicating the method used before partitions. The partition table has only one entry used, and it points to the start of the partition.
We have labeled this partition as being of the "DOS" type. Although it is only one of several possible partition types listed in Table 26.1, “Partition Types”, it is adequate for the purposes of this discussion.
Table 26.1, “Partition Types”, contains a listing of some popular (and obscure) partition types, along with their hexadecimal numeric values.

Table 26.1. Partition Types

Partition Type Value Partition Type Value
Empty 00 Novell Netware 386 65
DOS 12-bit FAT 01 PIC/IX 75
XENIX root 02 Old MINIX 80
XENIX usr 03 Linux/MINUX 81
DOS 16-bit <=32M 04 Linux swap 82
Extended 05 Linux native 83
DOS 16-bit >=32 06 Linux extended 85
OS/2 HPFS 07 Amoeba 93
AIX 08 Amoeba BBT 94
AIX bootable 09 BSD/386 a5
OS/2 Boot Manager 0a OpenBSD a6
Win95 FAT32 0b NEXTSTEP a7
Win95 FAT32 (LBA) 0c BSDI fs b7
Win95 FAT16 (LBA) 0e BSDI swap b8
Win95 Extended (LBA) 0f Syrinx c7
Venix 80286 40 CP/M db
Novell 51 DOS access e1
PPC PReP Boot 41 DOS R/O e3
GNU HURD 63 DOS secondary f2
Novell Netware 286 64 BBT ff

26.1.3. Partitions within Partitions — An Overview of Extended Partitions

Of course, over time it became obvious that four partitions would not be enough. As disk drives continued to grow, it became more and more likely that a person could configure four reasonably-sized partitions and still have disk space left over. There needed to be some way of creating more partitions.
Enter the extended partition. As you may have noticed in Table 26.1, “Partition Types”, there is an "Extended" partition type. It is this partition type that is at the heart of extended partitions.
When a partition is created and its type is set to "Extended," an extended partition table is created. In essence, the extended partition is like a disk drive in its own right — it has a partition table that points to one or more partitions (now called logical partitions, as opposed to the four primary partitions) contained entirely within the extended partition itself. Figure 26.7, “Disk Drive With Extended Partition”, shows a disk drive with one primary partition and one extended partition containing two logical partitions (along with some unpartitioned free space).
Disk Drive With Extended Partition

Figure 26.7. Disk Drive With Extended Partition

As this figure implies, there is a difference between primary and logical partitions — there can only be four primary partitions, but there is no fixed limit to the number of logical partitions that can exist. However, due to the way in which partitions are accessed in Linux, you should avoid defining more than 12 logical partitions on a single disk drive.
Now that we have discussed partitions in general, let us review how to use this knowledge to install Red Hat Enterprise Linux.

26.1.4. Making Room For Red Hat Enterprise Linux

The following list presents some possible scenarios you may face when attempting to repartition your hard disk:
  • Unpartitioned free space is available
  • An unused partition is available
  • Free space in an actively used partition is available
Let us look at each scenario in order.

Note

Keep in mind that the following illustrations are simplified in the interest of clarity and do not reflect the exact partition layout that you encounter when actually installing Red Hat Enterprise Linux.

26.1.4.1. Using Unpartitioned Free Space

In this situation, the partitions already defined do not span the entire hard disk, leaving unallocated space that is not part of any defined partition. Figure 26.8, “Disk Drive with Unpartitioned Free Space”, shows what this might look like.
Disk Drive with Unpartitioned Free Space

Figure 26.8. Disk Drive with Unpartitioned Free Space

In Figure 26.8, “Disk Drive with Unpartitioned Free Space”, 1 represents an undefined partition with unallocated space and 2 represents a defined partition with allocated space.
If you think about it, an unused hard disk also falls into this category. The only difference is that all the space is not part of any defined partition.
In any case, you can create the necessary partitions from the unused space. Unfortunately, this scenario, although very simple, is not very likely (unless you have just purchased a new disk just for Red Hat Enterprise Linux). Most pre-installed operating systems are configured to take up all available space on a disk drive (refer to Section 26.1.4.3, “Using Free Space from an Active Partition”).
Next, we will discuss a slightly more common situation.

26.1.4.2. Using Space from an Unused Partition

In this case, maybe you have one or more partitions that you do not use any longer. Perhaps you have dabbled with another operating system in the past, and the partition(s) you dedicated to it never seem to be used anymore. Figure 26.9, “Disk Drive With an Unused Partition”, illustrates such a situation.
Disk Drive With an Unused Partition

Figure 26.9. Disk Drive With an Unused Partition

In Figure 26.9, “Disk Drive With an Unused Partition”, 1 represents an unused partition and 2 represents reallocating an unused partition for Linux.
If you find yourself in this situation, you can use the space allocated to the unused partition. You first must delete the partition and then create the appropriate Linux partition(s) in its place. You can delete the unused partition and manually create new partitions during the installation process.

26.1.4.3. Using Free Space from an Active Partition

This is the most common situation. It is also, unfortunately, the hardest to handle. The main problem is that, even if you have enough free space, it is presently allocated to a partition that is already in use. If you purchased a computer with pre-installed software, the hard disk most likely has one massive partition holding the operating system and data.
Aside from adding a new hard drive to your system, you have two choices:
Destructive Repartitioning
Basically, you delete the single large partition and create several smaller ones. As you might imagine, any data you had in the original partition is destroyed. This means that making a complete backup is necessary. For your own sake, make two backups, use verification (if available in your backup software), and try to read data from your backup before you delete the partition.

Warning

If there was an operating system of some type installed on that partition, it needs to be reinstalled as well. Be aware that some computers sold with pre-installed operating systems may not include the CD-ROM media to reinstall the original operating system. The best time to notice if this applies to your system is before you destroy your original partition and its operating system installation.
After creating a smaller partition for your existing operating system, you can reinstall any software, restore your data, and start your Red Hat Enterprise Linux installation. Figure 26.10, “Disk Drive Being Destructively Repartitioned” shows this being done.
Disk Drive Being Destructively Repartitioned

Figure 26.10. Disk Drive Being Destructively Repartitioned

In Figure 26.10, “Disk Drive Being Destructively Repartitioned”, 1 represents before and 2 represents after.

Warning

As Figure 26.10, “Disk Drive Being Destructively Repartitioned”, shows, any data present in the original partition is lost without proper backup!
Non-Destructive Repartitioning
Here, you run a program that does the seemingly impossible: it makes a big partition smaller without losing any of the files stored in that partition. Many people have found this method to be reliable and trouble-free. What software should you use to perform this feat? There are several disk management software products on the market. Do some research to find the one that is best for your situation.
While the process of non-destructive repartitioning is rather straightforward, there are a number of steps involved:
  • Compress and backup existing data
  • Resize the existing partition
  • Create new partition(s)
Next we will look at each step in a bit more detail.
26.1.4.3.1. Compress existing data
As Figure 26.11, “Disk Drive Being Compressed”, shows, the first step is to compress the data in your existing partition. The reason for doing this is to rearrange the data such that it maximizes the available free space at the "end" of the partition.
Disk Drive Being Compressed

Figure 26.11. Disk Drive Being Compressed

In Figure 26.11, “Disk Drive Being Compressed”, 1 represents before and 2 represents after.
This step is crucial. Without it, the location of your data could prevent the partition from being resized to the extent desired. Note also that, for one reason or another, some data cannot be moved. If this is the case (and it severely restricts the size of your new partition(s)), you may be forced to destructively repartition your disk.
26.1.4.3.2. Resize the existing partition
Figure 26.12, “Disk Drive with Partition Resized”, shows the actual resizing process. While the actual result of the resizing operation varies depending on the software used, in most cases the newly freed space is used to create an unformatted partition of the same type as the original partition.
Disk Drive with Partition Resized

Figure 26.12. Disk Drive with Partition Resized

In Figure 26.12, “Disk Drive with Partition Resized”, 1 represents before and 2 represents after.
It is important to understand what the resizing software you use does with the newly freed space, so that you can take the appropriate steps. In the case we have illustrated, it would be best to delete the new DOS partition and create the appropriate Linux partition(s).
26.1.4.3.3. Create new partition(s)
As the previous step implied, it may or may not be necessary to create new partitions. However, unless your resizing software is Linux-aware, it is likely that you must delete the partition that was created during the resizing process. Figure 26.13, “Disk Drive with Final Partition Configuration”, shows this being done.
Disk Drive with Final Partition Configuration

Figure 26.13. Disk Drive with Final Partition Configuration

In Figure 26.13, “Disk Drive with Final Partition Configuration”, 1 represents before and 2 represents after.

Note

The following information is specific to x86-based computers only.
As a convenience to our customers, we provide the parted utility. This is a freely available program that can resize partitions.
If you decide to repartition your hard drive with parted, it is important that you be familiar with disk storage and that you perform a backup of your computer data. You should make two copies of all the important data on your computer. These copies should be to removable media (such as tape, CD-ROM, or diskettes), and you should make sure they are readable before proceeding.
Should you decide to use parted, be aware that after parted runs you are left with two partitions: the one you resized, and the one parted created out of the newly freed space. If your goal is to use that space to install Red Hat Enterprise Linux, you should delete the newly created partition, either by using the partitioning utility under your current operating system or while setting up partitions during installation.

26.1.5. Partition Naming Scheme

Linux refers to disk partitions using a combination of letters and numbers which may be confusing, particularly if you are used to the "C drive" way of referring to hard disks and their partitions. In the DOS/Windows world, partitions are named using the following method:
  • Each partition's type is checked to determine if it can be read by DOS/Windows.
  • If the partition's type is compatible, it is assigned a "drive letter." The drive letters start with a "C" and move on to the following letters, depending on the number of partitions to be labeled.
  • The drive letter can then be used to refer to that partition as well as the file system contained on that partition.
Red Hat Enterprise Linux uses a naming scheme that is more flexible and conveys more information than the approach used by other operating systems. The naming scheme is file-based, with file names in the form of /dev/xxyN.
Here is how to decipher the partition naming scheme:
/dev/
This is the name of the directory in which all device files reside. Since partitions reside on hard disks, and hard disks are devices, the files representing all possible partitions reside in /dev/.
xx
The first two letters of the partition name indicate the type of device on which the partition resides, usually either hd (for IDE disks) or sd (for SCSI disks).
y
This letter indicates which device the partition is on. For example, /dev/hda (the first IDE hard disk) or /dev/sdb (the second SCSI disk).
N
The final number denotes the partition. The first four (primary or extended) partitions are numbered 1 through 4. Logical partitions start at 5. So, for example, /dev/hda3 is the third primary or extended partition on the first IDE hard disk, and /dev/sdb6 is the second logical partition on the second SCSI hard disk.

Note

There is no part of this naming convention that is based on partition type; unlike DOS/Windows, all partitions can be identified under Red Hat Enterprise Linux. Of course, this does not mean that Red Hat Enterprise Linux can access data on every type of partition, but in many cases it is possible to access data on a partition dedicated to another operating system.
Keep this information in mind; it makes things easier to understand when you are setting up the partitions Red Hat Enterprise Linux requires.

26.1.6. Disk Partitions and Other Operating Systems

If your Red Hat Enterprise Linux partitions are sharing a hard disk with partitions used by other operating systems, most of the time you will have no problems. However, there are certain combinations of Linux and other operating systems that require extra care.

26.1.7. Disk Partitions and Mount Points

One area that many people new to Linux find confusing is the matter of how partitions are used and accessed by the Linux operating system. In DOS/Windows, it is relatively simple: Each partition gets a "drive letter." You then use the correct drive letter to refer to files and directories on its corresponding partition.
This is entirely different from how Linux deals with partitions and, for that matter, with disk storage in general. The main difference is that each partition is used to form part of the storage necessary to support a single set of files and directories. This is done by associating a partition with a directory through a process known as mounting. Mounting a partition makes its storage available starting at the specified directory (known as a mount point).
For example, if partition /dev/hda5 is mounted on /usr/, that would mean that all files and directories under /usr/ physically reside on /dev/hda5. So the file /usr/share/doc/FAQ/txt/Linux-FAQ would be stored on /dev/hda5, while the file /etc/gdm/custom.conf would not.
Continuing our example, it is also possible that one or more directories below /usr/ would be mount points for other partitions. For instance, a partition (say, /dev/hda7) could be mounted on /usr/local/, meaning that /usr/local/man/whatis would then reside on /dev/hda7 rather than /dev/hda5.

26.1.8. How Many Partitions?

At this point in the process of preparing to install Red Hat Enterprise Linux, you must give some consideration to the number and size of the partitions to be used by your new operating system. The question of "how many partitions" continues to spark debate within the Linux community and, without any end to the debate in sight, it is safe to say that there are probably as many partition layouts as there are people debating the issue.
Keeping this in mind, we recommend that, unless you have a reason for doing otherwise, you should at least create the following partitions: swap, /boot/ (or a /boot/efi/ partition for Itanium systems), a /var/ partition for Itanium systems, and / (root).


[11] Blocks really are consistently sized, unlike our illustrations. Keep in mind, also, that an average disk drive contains thousands of blocks. But for the purposes of this discussion, please ignore these minor discrepancies.

Part V. Basic System Recovery

When things go wrong, there are ways to fix problems. However, these methods require that you understand the system well. This section describes how to boot into rescue mode, single-user mode, and emergency mode, where you can use your own knowledge to repair the system..

Chapter 27. Basic System Recovery

When things go wrong, there are ways to fix problems. However, these methods require that you understand the system well. This chapter describes how to boot into rescue mode, single-user mode, and emergency mode, where you can use your own knowledge to repair the system.

27.1. Common Problems

You might need to boot into one of these recovery modes for any of the following reasons:
  • You are unable to boot normally into Red Hat Enterprise Linux (runlevel 3 or 5).
  • You are having hardware or software problems, and you want to get a few important files off of your system's hard drive.
  • You forgot the root password.

27.1.1. Unable to Boot into Red Hat Enterprise Linux

This problem is often caused by the installation of another operating system after you have installed Red Hat Enterprise Linux. Some other operating systems assume that you have no other operating system(s) on your computer. They overwrite the Master Boot Record (MBR) that originally contained the GRUB boot loader. If the boot loader is overwritten in this manner, you cannot boot Red Hat Enterprise Linux unless you can get into rescue mode and reconfigure the boot loader.
Another common problem occurs when using a partitioning tool to resize a partition or create a new partition from free space after installation, and it changes the order of your partitions. If the partition number of your / partition changes, the boot loader might not be able to find it to mount the partition. To fix this problem, boot in rescue mode and modify the /boot/grub/grub.conf file.
For instructions on how to reinstall the GRUB boot loader from a rescue environment, refer to Section 27.2.1, “Reinstalling the Boot Loader”.

27.1.2. Hardware/Software Problems

This category includes a wide variety of different situations. Two examples include failing hard drives and specifying an invalid root device or kernel in the boot loader configuration file. If either of these occur, you might not be able to reboot into Red Hat Enterprise Linux. However, if you boot into one of the system recovery modes, you might be able to resolve the problem or at least get copies of your most important files.

27.1.3. Root Password

What can you do if you forget your root password? To reset it to a different password, boot into rescue mode or single-user mode, and use the passwd command to reset the root password.

27.2. Booting into Rescue Mode

Rescue mode provides the ability to boot a small Red Hat Enterprise Linux environment entirely from CD-ROM, or some other boot method, instead of the system's hard drive.
As the name implies, rescue mode is provided to rescue you from something. During normal operation, your Red Hat Enterprise Linux system uses files located on your system's hard drive to do everything — run programs, store your files, and more.
However, there may be times when you are unable to get Red Hat Enterprise Linux running completely enough to access files on your system's hard drive. Using rescue mode, you can access the files stored on your system's hard drive, even if you cannot actually run Red Hat Enterprise Linux from that hard drive.
To boot into rescue mode, you must be able to boot the system using one of the following methods[12]:
  • By booting the system from an installation boot CD-ROM.
  • By booting the system from other installation boot media, such as USB flash devices.
  • By booting the system from the Red Hat Enterprise Linux CD-ROM #1.
Once you have booted using one of the described methods, add the keyword rescue as a kernel parameter. For example, for an x86 system, type the following command at the installation boot prompt:
linux rescue
You are prompted to answer a few basic questions, including which language to use. It also prompts you to select where a valid rescue image is located. Select from Local CD-ROM, Hard Drive, NFS image, FTP, or HTTP. The location selected must contain a valid installation tree, and the installation tree must be for the same version of Red Hat Enterprise Linux as the Red Hat Enterprise Linux disk from which you booted. If you used a boot CD-ROM or other media to start rescue mode, the installation tree must be from the same tree from which the media was created. For more information about how to setup an installation tree on a hard drive, NFS server, FTP server, or HTTP server, refer to the earlier section of this guide.
If you select a rescue image that does not require a network connection, you are asked whether or not you want to establish a network connection. A network connection is useful if you need to backup files to a different computer or install some RPM packages from a shared network location, for example.
The following message is displayed:
The rescue environment will now attempt to find your Linux installation and mount it under the directory /mnt/sysimage. You can then make any changes required to your system. If you want to proceed with this step choose 'Continue'. You can also choose to mount your file systems read-only instead of read-write by choosing 'Read-only'. If for some reason this process fails you can choose 'Skip' and this step will be skipped and you will go directly to a command shell.
If you select Continue, it attempts to mount your file system under the directory /mnt/sysimage/. If it fails to mount a partition, it notifies you. If you select Read-Only, it attempts to mount your file system under the directory /mnt/sysimage/, but in read-only mode. If you select Skip, your file system is not mounted. Choose Skip if you think your file system is corrupted.
Once you have your system in rescue mode, a prompt appears on VC (virtual console) 1 and VC 2 (use the Ctrl-Alt-F1 key combination to access VC 1 and Ctrl-Alt-F2 to access VC 2):
sh-3.00b#
If you selected Continue to mount your partitions automatically and they were mounted successfully, you are in single-user mode.
Even if your file system is mounted, the default root partition while in rescue mode is a temporary root partition, not the root partition of the file system used during normal user mode (runlevel 3 or 5). If you selected to mount your file system and it mounted successfully, you can change the root partition of the rescue mode environment to the root partition of your file system by executing the following command:
chroot /mnt/sysimage
This is useful if you need to run commands such as rpm that require your root partition to be mounted as /. To exit the chroot environment, type exit to return to the prompt.
If you selected Skip, you can still try to mount a partition or LVM2 logical volume manually inside rescue mode by creating a directory such as /foo, and typing the following command:
mount -t ext3 /dev/mapper/VolGroup00-LogVol02 /foo
In the above command, /foo is a directory that you have created and /dev/mapper/VolGroup00-LogVol02 is the LVM2 logical volume you want to mount. If the partition is of type ext2, replace ext3 with ext2.
If you do not know the names of all physical partitions, use the following command to list them:
fdisk -l
If you do not know the names of all LVM2 physical volumes, volume groups, or logical volumes, use the following commands to list them:
pvdisplay
vgdisplay
lvdisplay
From the prompt, you can run many useful commands, such as:
  • ssh, scp, and ping if the network is started
  • dump and restore for users with tape drives
  • parted and fdisk for managing partitions
  • rpm for installing or upgrading software
  • joe for editing configuration files

    Note

    If you try to start other popular editors such as emacs, pico, or vi, the joe editor is started.

27.2.1. Reinstalling the Boot Loader

In many cases, the GRUB boot loader can mistakenly be deleted, corrupted, or replaced by other operating systems.
The following steps detail the process on how GRUB is reinstalled on the master boot record:
  • Boot the system from an installation boot medium.
  • Type linux rescue at the installation boot prompt to enter the rescue environment.
  • Type chroot /mnt/sysimage to mount the root partition.
  • Type /usr/sbin/grub-install bootpart to reinstall the GRUB boot loader, where bootpart is the boot partition (typically, /dev/sda).
  • Review the /boot/grub/grub.conf file, as additional entries may be needed for GRUB to control additional operating systems.
  • Reboot the system.

27.3. Booting into Single-User Mode

One of the advantages of single-user mode is that you do not need a boot CD-ROM; however, it does not give you the option to mount the file systems as read-only or not mount them at all.
If your system boots, but does not allow you to log in when it has completed booting, try single-user mode.
In single-user mode, your computer boots to runlevel 1. Your local file systems are mounted, but your network is not activated. You have a usable system maintenance shell. Unlike rescue mode, single-user mode automatically tries to mount your file system. Do not use single-user mode if your file system cannot be mounted successfully. You cannot use single-user mode if the runlevel 1 configuration on your system is corrupted.
On an x86 system using GRUB, use the following steps to boot into single-user mode:
  1. At the GRUB splash screen at boot time, press any key to enter the GRUB interactive menu.
  2. Select Red Hat Enterprise Linux with the version of the kernel that you wish to boot and type a to append the line.
  3. Go to the end of the line and type single as a separate word (press the Spacebar and then type single). Press Enter to exit edit mode.

27.4. Booting into Emergency Mode

In emergency mode, you are booted into the most minimal environment possible. The root file system is mounted read-only and almost nothing is set up. The main advantage of emergency mode over single-user mode is that the init files are not loaded. If init is corrupted or not working, you can still mount file systems to recover data that could be lost during a re-installation.
To boot into emergency mode, use the same method as described for single-user mode in Section 27.3, “Booting into Single-User Mode” with one exception, replace the keyword single with the keyword emergency.


[12] Refer to the earlier sections of this guide for more details.

Chapter 28. Rescue Mode on POWER Systems

You can use the installation disks in rescue mode, in case your system does not boot. Rescue mode gives you access to the disk partitions on your system so you can make any changes necessary to rescue your installation.
To boot in rescue mode on IBM System i with power control NWSD , follow the instructions for booting the installation program, with this change: In the NWSD, set the IPL parameters field to 'rescue' (including the quotes), or to 'dd rescue' if you need to load the SCSI driver. On other systems, specify the rescue or dd rescue (without quotes) after the default kernel name at the YABOOT prompt.
After the Language Selection screen (Section 12.13, “Language Selection”), the installation program attempts to mount the disk partitions on your system. It then presents you with a shell prompt where you can make the changes you need. These changes may include storing the kernel and command line into the IPL source, as described in the Installation Complete section (Section 12.26, “Installation Complete”).
When your changes are complete, you can exit the shell using exit 0. This causes a reboot from the C side. To reboot from the A or B side or from *NWSSTG, you should vary off the system instead of exiting the shell.

28.1. Special Considerations for Accessing the SCSI Utilities from Rescue Mode

If your system uses Native DASD disks, you may need access to the SCSI utilities from rescue mode. These utilities are located on the driver disc CD. The driver disc CD cannot be mounted from rescue mode unless special steps are taken. These steps are described below.
If you have a second CD-ROM drive assigned to your Linux system, you can mount the driver disc CD in the second drive.
If you have only one CD-ROM drive, you must set up an NFS boot, using the following steps:
  1. Boot from the CD-ROM with the linux rescue askmethod command. This allows you to manually select NFS as the source of your rescue media instead of defaulting to the CD-ROM drive.
  2. Copy the first installation disc onto a file system of another Linux system.
  3. Make this copy of the installation disc available through NFS or FTP.
  4. Vary off or power down the system you need to rescue. Set its IPL parameters as instructed for booting the Installation discs in rescue mode, except that the IPL source should point to the copy of boot.img on your IFS (from step 1, above).
  5. Make sure the installation disc is not in your CD-ROM drive.
  6. IPL the Linux system.
  7. Follow the prompts as described in Chapter 28, Rescue Mode on POWER Systems. An additional prompt for the installation source appears. Select NFS or FTP (as appropriate) and complete the following network configuration screen.
  8. When the Linux system has booted into rescue mode, the CD-ROM drive is available for use and you can mount the driver media to access the SCSI utilities.

Part VI. Advanced Installation and Deployment

The Red Hat Enterprise Linux Installation Guide discusses the installation of Red Hat Enterprise Linux and some basic post-installation troubleshooting. However, advanced installation options are also covered in this manual. This part provides instructions for kickstart (an automated installation technique)and all related tools. Use this part in conjunction with the first part of the Red Hat Enterprise Linux Installation Guide to perform any of these advanced installation tasks.

Chapter 29. Disk Encryption Guide

Note

Red Hat Enterprise Linux 5.3 now contains support during installation for file system encryption. This is not supported for earlier versions of Red Hat Enterprise Linux.

29.1. What is block device encryption?

Block device encryption protects the data on a block device by encrypting it. To access the device's decrypted contents, a user must provide a passphrase or key as authentication. This provides additional security beyond existing OS security mechanisms in that it protects the device's contents even if it has been physically removed from the system.

29.2. Encrypting block devices using dm-crypt/LUKS

Linux Unified Key Setup (LUKS) is a specification for block device encryption. It establishes an on-disk format for the data, as well as a passphrase/key management policy.
LUKS uses the kernel device mapper subsystem via the dm-crypt module. This arrangement provides a low-level mapping that handles encryption and decryption of the device's data. User-level operations, such as creating and accessing encrypted devices, are accomplished through the use of the cryptsetup utility.

29.2.1. Overview of LUKS

  • What LUKS does:
    • LUKS encrypts entire block devices
      • LUKS is thereby well-suited for protecting the contents of mobile devices such as:
        • Removable storage media
        • Laptop disk drives
    • The underlying contents of the encrypted block device are arbitrary.
      • This makes it useful for encrypting swap devices.
      • This can also be useful with certain databases that use specially formatted block devices for data storage.
    • LUKS uses the existing device mapper kernel subsystem.
      • This is the same subsystem used by LVM, so it is well tested.
    • LUKS provides passphrase strengthening.
      • This protects against dictionary attacks.
    • LUKS devices contain multiple key slots.
      • This allows users to add backup keys/passphrases.
  • What LUKS does not do:
    • LUKS is not well-suited for applications requiring many (more than eight) users to have distinct access keys to the same device.
    • LUKS is not well-suited for applications requiring file-level encryption.
For more information on LUKS, refer to http://code.google.com/p/cryptsetup/

29.2.2. How will I access the encrypted devices after installation? (System Startup)

During system startup you will be presented with a passphrase prompt. After the correct passphrase has been provided the system will continue to boot normally. If you used different passphrases for multiple encrypted devices you may need to enter more than one passphrase during the startup.

Note

Consider using the same passphrase for all encrypted block devices in a given system. This will simplify system startup and you will have fewer passphrases to remember. Just make sure you choose a good passphrase!

29.2.3. Choosing a Good Passphrase

While dm-crypt/LUKS supports both keys and passphrases, the anaconda installer only supports the use of passphrases for creating and accessing encrypted block devices during installation.
LUKS does provide passphrase strengthening but it is still a good idea to choose a good (meaning "difficult to guess") passphrase. Note the use of the term "passphrase", as opposed to the term "password". This is intentional. Providing a phrase containing multiple words to increase the security of your data is important.

29.3. Creating Encrypted Block Devices in Anaconda

You can create encrypted devices during system installation. This allows you to easily configure a system with encrypted partitions.
To enable block device encryption, check the "Encrypt System" checkbox when selecting automatic partitioning or the "Encrypt" checkbox when creating an individual partition, software RAID array, or logical volume. After you finish partitioning, you will be prompted for an encryption passphrase. This passphrase will be required to access the encrypted devices. If you have pre-existing LUKS devices and provided correct passphrases for them earlier in the install process the passphrase entry dialog will also contain a checkbox. Checking this checkbox indicates that you would like the new passphrase to be added to an available slot in each of the pre-existing encrypted block devices.

Important

Devices encrypted with LUKS can share a global passphrase. When a system contains more than two encrypted block devices, anaconda offers you the option to set a global passphrase for them. However, although anaconda can set this passphrase correctly, the use of global passphrases is not supported by the init scripts in Red Hat Enterprise Linux 5.
Therefore, even if you set a global passphrase during installation, you must still supply individual passphrases for each encrypted block device every time that the system boots.

Note

Checking the "Encrypt System" checkbox on the "Automatic Partitioning" screen and then choosing "Create custom layout" does not cause any block devices to be encrypted automatically.

Note

You can use kickstart to set a separate passphrase for each new encrypted block device.

29.3.1. What Kinds of Block Devices Can Be Encrypted?

Most types of block devices can be encrypted using LUKS. From anaconda you can encrypt partitions, LVM physical volumes, LVM logical volumes, and software RAID arrays.

29.4. Creating Encrypted Block Devices on the Installed System After Installation

Encrypted block devices can be created and configured after installation.

29.4.1. Create the block devices

Create the block devices you want to encrypt by using parted, pvcreate, lvcreate and mdadm.

29.4.2. Optional: Fill the device with random data

Filling <device> (eg: /dev/sda3) with random data before encrypting it greatly increases the strength of the encryption. The downside is that it can take a very long time.

Warning

The commands below will destroy any existing data on the device.
  • The best way, which provides high quality random data but takes a long time (several minutes per gigabyte on most systems):
    dd if=/dev/urandom of=<device>
  • Fastest way, which provides lower quality random data:
    badblocks -c 10240 -s -w -t random -v <device>

29.4.3. Format the device as a dm-crypt/LUKS encrypted device

Warning

The command below will destroy any existing data on the device.
cryptsetup luksFormat <device>

Note

For more information, read the cryptsetup(8) man page.
After supplying the passphrase twice the device will be formatted for use. To verify, use the following command:
cryptsetup isLuks <device> && echo Success
To see a summary of the encryption information for the device, use the following command:
cryptsetup luksDump <device>

29.4.4. Create a mapping to allow access to the device's decrypted contents

To access the device's decrypted contents, a mapping must be established using the kernel device-mapper.
It is useful to choose a meaningful name for this mapping. LUKS provides a UUID (Universally Unique Identifier) for each device. This, unlike the device name (eg: /dev/sda3), is guaranteed to remain constant as long as the LUKS header remains intact. To find a LUKS device's UUID, run the following command:
cryptsetup luksUUID <device>
An example of a reliable, informative and unique mapping name would be luks-<uuid>, where <uuid> is replaced with the device's LUKS UUID (eg: luks-50ec957a-5b5a-47ee-85e6-f8085bbc97a8). This naming convention might seem unwieldy but is it not necessary to type it often.
cryptsetup luksOpen <device> <name>
There should now be a device node, /dev/mapper/<name>, which represents the decrypted device. This block device can be read from and written to like any other unencrypted block device.
To see some information about the mapped device, use the following command:
dmsetup info <name>

Note

For more information, read the dmsetup(8) man page.

29.4.5. Create filesystems on the mapped device, or continue to build complex storage structures using the mapped device

Use the mapped device node (/dev/mapper/<name>) as any other block device. To create an ext2 filesystem on the mapped device, use the following command:
mke2fs /dev/mapper/<name>
To mount this filesystem on /mnt/test, use the following command:

Important

The directory /mnt/test must exist before executing this command.
mount /dev/mapper/<name> /mnt/test

29.4.6. Add the mapping information to /etc/crypttab

In order for the system to set up a mapping for the device, an entry must be present in the /etc/crypttab file. If the file doesn't exist, create it and change the owner and group to root (root:root) and change the mode to 0744. Add a line to the file with the following format:
<name>  <device>  none
The <device> field should be given in the form "UUID=<luks_uuid>", where <luks_uuid> is the LUKS uuid as given by the command cryptsetup luksUUID <device>. This ensures the correct device will be identified and used even if the device node (eg: /dev/sda5) changes.

Note

For details on the format of the /etc/crypttab file, read the crypttab(5) man page.

29.4.7. Add an entry to /etc/fstab

Add an entry to /etc/fstab. This is only necessary if you want to establish a persistent association between the device and a mountpoint. Use the decrypted device, /dev/mapper/<name> in the /etc/fstab file.
In many cases it is desirable to list devices in /etc/fstab by UUID or by a filesystem label. The main purpose of this is to provide a constant identifier in the event that the device name (eg: /dev/sda4) changes. LUKS device names in the form of /dev/mapper/luks-<luks_uuid> are based only on the device's LUKS UUID, and are therefore guaranteed to remain constant. This fact makes them suitable for use in /etc/fstab.

Note

For details on the format of the /etc/fstab file, read the fstab(5) man page.

29.5. Common Post-Installation Tasks

The following sections are about common post-installation tasks.

29.5.1. Set a randomly generated key as an additional way to access an encrypted block device

These sections are about generating keys and adding keys.

29.5.1.1. Generate a key

This will generate a 256-bit key in the file $HOME/keyfile.
		dd if=/dev/urandom of=$HOME/keyfile bs=32 count=1
		chmod 600 $HOME/keyfile

29.5.1.2. Add the key to an available keyslot on the encrypted device

cryptsetup luksAddKey <device> ~/keyfile

29.5.2. Add a new passphrase to an existing device

cryptsetup luksAddKey <device>
After being prompted for any one of the existing passphrases for authentication, you will be prompted to enter the new passphrase.

29.5.3. Remove a passphrase or key from a device

cryptsetup luksRemoveKey <device>
You will be prompted for the passphrase you wish to remove and then for any one of the remaining passphrases for authentication.

Chapter 30. Installing Through VNC

Many enterprise customers perform interactive installations on systems in datacenters. These systems are often, but not always, installed in a rack environment and do not have a display, keyboard, or mouse. Additionally, a lot of these systems even lack the ability to connect a graphical display. Given that enterprise hardware rarely needs that ability at the physical system, this hardware configuration is acceptable.
The Red Hat Enterprise Linux installer (anaconda) offers users two interactive modes of operation. The original mode is a text-based interface. The newer mode uses GTK+ and runs in the X Window environment. The purpose of this document is to explain how the graphical installation mode can be used in enterprise environments, even when the system lacks a proper display and input devices typically associated with a workstation.
The primary driver behind the document is to encourage use of the graphical installer, even in enterprise environments. The text mode environment lacks a lot of capabilities found in the graphical mode. Many users still feel that the text mode interface provides them with additional power or configuration ability not found in the graphical version. The opposite is true. Much less development effort is put in to the text mode environment and specific things (e.g., LVM configuration) are deliberately left out of the text mode environment. The reasons for this are:
  • Less screen real estate for creating user interfaces similar to those found in the graphical mode.
  • Difficult internationalization support.
  • Desire to maintain a single interactive installation code path.
All of these reasons and more are why you, the enterprise customer, should be making using of the Virtual Network Computing (VNC) mode offered in anaconda. VNC allows the graphical mode of the installer to run locally, but display on a system connected to the network.

30.1. VNC Viewer

Performing a VNC installation requires a VNC viewer running on your workstation or other terminal computer. Locations where you might want a VNC viewer installed:
  • Your workstation
  • Laptop on a datacenter crash cart
VNC is open source software licensed under the GNU General Public License. Versions exist for Linux, Windows, and MacOS X. Here are some recommended VNC viewers:
  • vncviewer is available on Red Hat Enterprise Linux by installing the vnc package:
    # yum install vnc
  • TightVNC is available for Windows at http://www.tightvnc.com/
  • MacOS X includes built-in VNC support as of version 10.5. In the Finder, click the Go menu and choose Connect to Server. In the server address field, you can type vnc://SERVER:DISPLAY, where SERVER is the IP address or DNS host name of the VNC server you wish to connect to and DISPLAY is the VNC display number (usually 1), and click Connect.
Once you have verified you have a VNC viewer available, it's time to start the installation.

30.2. VNC Modes in Anaconda

Anaconda offers two modes for VNC installation. The mode you select will depend on the network configuration in your environment.

30.2.1. Direct Mode

Direct mode VNC in anaconda is when the client initiates a connection to the VNC server running in anaconda. Anaconda will tell you when to initiate this connection in the VNC viewer. Direct mode can be activated by either of the following commands:
  • Specify vnc as a boot argument.
  • Specify the vnc command in the kickstart file used for installation.
When you activate VNC mode, anaconda will complete the first stage of the installer and then start VNC to run the graphical installer. The installer will display a message on the console in the following format:
Running anaconda VERSION, the PRODUCT system installer - please wait...
Anaconda will also tell you the IP address and display number to use in your VNC viewer. At this point, you need to start the VNC viewer and connect to the target system to continue the installation. The VNC viewer will present anaconda to you in graphical mode.
There are some disadvantages to direct mode, including:
  • Requires visual access to the system console to see the IP address and port to connect the VNC viewer to.
  • Requires interactive access to the system console to complete the first stage of the installer.
If either of these disadvantages would prevent you from using direct mode VNC in anaconda, then connect mode is probably more suited to your environment.

30.2.2. Connect Mode

Certain firewall configurations or instances where the target system is configured to obtain a dynamic IP address may cause trouble with the direct VNC mode in anaconda. In addition, if you lack a console on the target system to see the message that tells you the IP address to connect to, then you will not be able to continue the installation.
The VNC connect mode changes how VNC is started. Rather than anaconda starting up and waiting for you to connect, the VNC connect mode allows anaconda to automatically connect to your view. You won't need to know the IP address of the target system in this case.
To activate the VNC connect mode, pass the vncconnect boot parameter:
boot: linux vncconnect=HOST
Replace HOST with your VNC viewer's IP address or DNS host name. Before starting the installation process on the target system, start up your VNC viewer and have it wait for an incoming connection.
Start the installation and when your VNC viewer displays the graphical installer, you are ready to go.

30.3. Installation Using VNC

Now that you have installed a VNC viewer application and selected a VNC mode for use in anaconda, you are ready to begin the installation.

30.3.1. Installation Example

The easiest way to perform an installation using VNC is to connect another computer directly to the network port on the target system. The laptop on a datacenter crash cart usually fills this role. If you are performing your installation this way, make sure you follow these steps:
  1. Connect the laptop or other workstation to the target system using a crossover cable. If you are using regular patch cables, make sure you connect the two systems using a small hub or switch. Most recent Ethernet interfaces will automatically detect if they need to be crossover or not, so it may be possible to connect the two systems directly using a regular patch cable.
  2. Configure the VNC viewer system to use a RFC 1918 address with no gateway. This private network connection will only be used for the purpose of installation. Configure the VNC viewer system to be 192.168.100.1/24. If that address is in use, just pick something else in the RFC 1918 address space that is available to you.
  3. Start the RHEL installation on the target system.
    1. Booting the installation DVD or CD.
      If booting the installation media (CD or DVD), make sure vnc is passed as a boot parameter. To add the vnc parameter, you will need a console attached to the target system that allows you to interact with the boot process. Enter the following at the prompt:
      boot: linux vnc
    2. Boot over the network.
      If the target system is configured with a static IP address, add the vnc command to the kickstart file. If the target system is using DHCP, add vncconnect=HOST to the boot arguments for the target system. HOST is the IP address or DNS host name of the VNC viewer system. Enter the following at the prompt:
      boot: linux vncconnect=HOST
  4. When prompted for the network configuration on the target system, assign it an available RFC 1918 address in the same network you used for the VNC viewer system. For example, 192.168.100.2/24.

    Note

    This IP address is only used during installation. You will have an opportunity to configure the final network settings, if any, later in the installer.
  5. Once the installer indicates it is starting anaconda, you will be instructed to connect to the system using the VNC viewer. Connect to the viewer and follow the graphical installation mode instructions found in the product documentation.

30.3.2. Kickstart Considerations

If your target system will be booting over the network, VNC is still available. Just add the vnc command to the kickstart file for the system. You will be able to connect to the target system using your VNC viewer and monitor the installation progress. The address to use is the one the system is configured with via the kickstart file.
If you are using DHCP for the target system, the reverse vncconnect method may work better for you. Rather than adding the vnc boot parameter to the kickstart file, add the vncconnect=HOST parameter to the list of boot arguments for the target system. For HOST, put the IP address or DNS host name of the VNC viewer system. See the next section for more details on using the vncconnect mode.

30.3.3. Firewall Considerations

If you are performing the installation where the VNC viewer system is a workstation on a different subnet from the target system, you may run in to network routing problems. VNC works fine so long as your viewer system has a route to the target system and ports 5900 and 5901 are open. If your environment has a firewall, make sure ports 5900 and 5901 are open between your workstation and the target system.
In addition to passing the vnc boot parameter, you may also want to pass the vncpassword parameter in these scenarios. While the password is sent in plain text over the network, it does provide an extra step before a viewer can connect to a system. Once the viewer connects to the target system over VNC, no other connections are permitted. These limitations are usually sufficient for installation purposes.

Important

Be sure to use a temporary password for the vncpassword option. It should not be a password you use on any systems, especially a real root password.
If you continue to have trouble, consider using the vncconnect parameter. In this mode of operation, you start the viewer on your system first telling it to listen for an incoming connection. Pass vncconnect=HOST at the boot prompt and the installer will attempt to connect to the specified HOST (either a hostname or IP address).

30.4. References

Chapter 31. Kickstart Installations

31.1. What are Kickstart Installations?

Many system administrators would prefer to use an automated installation method to install Red Hat Enterprise Linux on their machines. To answer this need, Red Hat created the kickstart installation method. Using kickstart, a system administrator can create a single file containing the answers to all the questions that would normally be asked during a typical installation.
Kickstart files can be kept on a single server system and read by individual computers during the installation. This installation method can support the use of a single kickstart file to install Red Hat Enterprise Linux on multiple machines, making it ideal for network and system administrators.
Kickstart provides a way for users to automate a Red Hat Enterprise Linux installation.

31.2. How Do You Perform a Kickstart Installation?

Kickstart installations can be performed using a local CD-ROM, a local hard drive, or via NFS, FTP, or HTTP.
To use kickstart, you must:
  1. Create a kickstart file.
  2. Create a boot media with the kickstart file or make the kickstart file available on the network.
  3. Make the installation tree available.
  4. Start the kickstart installation.
This chapter explains these steps in detail.

31.3. Creating the Kickstart File

The kickstart file is a simple text file, containing a list of items, each identified by a keyword. You can create it by using the Kickstart Configurator application, or writing it from scratch. The Red Hat Enterprise Linux installation program also creates a sample kickstart file based on the options that you selected during installation. It is written to the file /root/anaconda-ks.cfg. You should be able to edit it with any text editor or word processor that can save files as ASCII text.
First, be aware of the following issues when you are creating your kickstart file:
  • Sections must be specified in order. Items within the sections do not have to be in a specific order unless otherwise specified. The section order is:
  • Items that are not required can be omitted.
  • Omitting any required item results in the installation program prompting the user for an answer to the related item, just as the user would be prompted during a typical installation. Once the answer is given, the installation continues unattended (unless it finds another missing item).
  • Lines starting with a pound (also known as hash) sign (#) are treated as comments and are ignored.
  • For kickstart upgrades, the following items are required:
    • Language
    • Installation method
    • Device specification (if device is needed to perform the installation)
    • Keyboard setup
    • The upgrade keyword
    • Boot loader configuration
    If any other items are specified for an upgrade, those items are ignored (note that this includes package selection).

31.4. Kickstart Options

The following options can be placed in a kickstart file. If you prefer to use a graphical interface for creating your kickstart file, use the Kickstart Configurator application. Refer to Chapter 32, Kickstart Configurator for details.

Note

If the option is followed by an equals mark (=), a value must be specified after it. In the example commands, options in brackets ([]) are optional arguments for the command.
autopart (optional)
Automatically create partitions — 1 GB or more root (/) partition, a swap partition, and an appropriate boot partition for the architecture. One or more of the default partition sizes can be redefined with the part directive.
  • --encrypted — Should all devices with support be encrypted by default? This is equivalent to checking the Encrypt checkbox on the initial partitioning screen.
  • --passphrase= — Provide a default system-wide passphrase for all encrypted devices.
ignoredisk (optional)
Causes the installer to ignore the specified disks. If the target system contains read-only devices, they must be specified with ignoredisk or the installation will stop and prompt for whether it should ignore the device.
ignoredisk is useful if you use autopartition and want to be sure that some disks are ignored. For example, without ignoredisk, attempting to deploy on a SAN-cluster the kickstart would fail, as the installer detects passive paths to the SAN that return no partition table. The --only-use option specifies that only the disks listed will be used during installation.
The ignoredisk option is also useful if you have multiple paths to your disks.
The syntax is:
ignoredisk --drives=drive1,drive2,...
where driveN is one of sda, sdb,..., hda,... etc.
  • --only-use — specifies a list of disks for the installer to use. All other disks are ignored. For example, to use disk sda during installation and ignore all other disks:
    ignoredisk --only-use=sda
autostep (optional)
Similar to interactive except it goes to the next screen for you. It is used mostly for debugging and should not be used when deploying a system because it may disrupt package installation.
  • --autoscreenshot — Take a screenshot at every step during installation and copy the images over to /root/anaconda-screenshots after installation is complete. This is most useful for documentation.
auth or authconfig (required)
Sets up the authentication options for the system. It is similar to the authconfig command, which can be run after the install. By default, passwords are normally encrypted and are not shadowed.
  • --enablemd5 — Use md5 encryption for user passwords.
  • --enablenis — Turns on NIS support. By default, --enablenis uses whatever domain it finds on the network. A domain should almost always be set by hand with the --nisdomain= option.
  • --nisdomain= — NIS domain name to use for NIS services.
  • --nisserver= — Server to use for NIS services (broadcasts by default).
  • --useshadow or --enableshadow — Use shadow passwords.
  • --enableldap — Turns on LDAP support in /etc/nsswitch.conf, allowing your system to retrieve information about users (UIDs, home directories, shells, etc.) from an LDAP directory. To use this option, you must install the nss_ldap package. You must also specify a server and a base DN (distinguished name) with --ldapserver= and --ldapbasedn=.
  • --enableldapauth — Use LDAP as an authentication method. This enables the pam_ldap module for authentication and changing passwords, using an LDAP directory. To use this option, you must have the nss_ldap package installed. You must also specify a server and a base DN with --ldapserver= and --ldapbasedn=.
  • --ldapserver= — If you specified either --enableldap or --enableldapauth, use this option to specify the name of the LDAP server to use. This option is set in the /etc/ldap.conf file.
  • --ldapbasedn= — If you specified either --enableldap or --enableldapauth, use this option to specify the DN in your LDAP directory tree under which user information is stored. This option is set in the /etc/ldap.conf file.
  • --enableldaptls — Use TLS (Transport Layer Security) lookups. This option allows LDAP to send encrypted usernames and passwords to an LDAP server before authentication.
  • --enablekrb5 — Use Kerberos 5 for authenticating users. Kerberos itself does not know about home directories, UIDs, or shells. If you enable Kerberos, you must make users' accounts known to this workstation by enabling LDAP, NIS, or Hesiod or by using the /usr/sbin/useradd command. If you use this option, you must have the pam_krb5 package installed.
  • --krb5realm= — The Kerberos 5 realm to which your workstation belongs.
  • --krb5kdc= — The KDC (or KDCs) that serve requests for the realm. If you have multiple KDCs in your realm, separate their names with commas (,).
  • --krb5adminserver= — The KDC in your realm that is also running kadmind. This server handles password changing and other administrative requests. This server must be run on the master KDC if you have more than one KDC.
  • --enablehesiod — Enable Hesiod support for looking up user home directories, UIDs, and shells. More information on setting up and using Hesiod on your network is in /usr/share/doc/glibc-2.x.x/README.hesiod, which is included in the glibc package. Hesiod is an extension of DNS that uses DNS records to store information about users, groups, and various other items.
  • --hesiodlhs — The Hesiod LHS ("left-hand side") option, set in /etc/hesiod.conf. This option is used by the Hesiod library to determine the name to search DNS for when looking up information, similar to LDAP's use of a base DN.
  • --hesiodrhs — The Hesiod RHS ("right-hand side") option, set in /etc/hesiod.conf. This option is used by the Hesiod library to determine the name to search DNS for when looking up information, similar to LDAP's use of a base DN.

    Note

    To look up user information for "jim", the Hesiod library looks up jim.passwd<LHS><RHS>, which should resolve to a TXT record that looks like what his passwd entry would look like (jim:*:501:501:Jungle Jim:/home/jim:/bin/bash). For groups, the situation is identical, except jim.group<LHS><RHS> would be used.
    Looking up users and groups by number is handled by making "501.uid" a CNAME for "jim.passwd", and "501.gid" a CNAME for "jim.group". Note that the library does not place a period . in front of the LHS and RHS values when performing a search. Therefore the LHS and RHS values need to have a period placed in front of them in order if they require this.
  • --enablesmbauth — Enables authentication of users against an SMB server (typically a Samba or Windows server). SMB authentication support does not know about home directories, UIDs, or shells. If you enable SMB, you must make users' accounts known to the workstation by enabling LDAP, NIS, or Hesiod or by using the /usr/sbin/useradd command to make their accounts known to the workstation. To use this option, you must have the pam_smb package installed.
  • --smbservers= — The name of the server(s) to use for SMB authentication. To specify more than one server, separate the names with commas (,).
  • --smbworkgroup= — The name of the workgroup for the SMB servers.
  • --enablecache — Enables the nscd service. The nscd service caches information about users, groups, and various other types of information. Caching is especially helpful if you choose to distribute information about users and groups over your network using NIS, LDAP, or hesiod.
  • --passalgo — Enables SHA256 or SHA512 hashing for passphrases. Use --passalgo=sha256 or --passalgo=sha512 and remove the --enablemd5 if present.
bootl