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Chapter 9. Boot Devices

Automated installation (or kickstart) is an essential part of efficient system provisioning. This chapter describes how to prepare different types of boot media for use with kickstarting clients.
For more detailed information on using kickstart for provisioning, see the RHN Satellite Server Getting Started Guide.
The Red Hat Enterprise Linux CD boot image boot.iso is a required prerequisite for creating boot devices. Make sure that this is available somewhere on the system and take note of its location.

Procedure 9.1. CD Boot Media

Note

The backslash "\" is used below to represent a continuation of one line at the shell prompt.
  1. Create a working directory for the boot image:
    mkdir -p temp cd/isolinux
    
  2. Mount the boot image to the temp directory:
    mount -o loop boot.iso temp
    
  3. Copy the required files for a CD Boot Media device to the previously created directory:
    cp -aP temp/isolinux/* cd/isolinux/
    
  4. Unmount the temp directory and change the permissions on the cd directory to be readable and writable to the user:
    umount temp
    chmod -R u+rw cd
    
  5. Change to the ./cd directory:
    cd ./cd
    
  6. Copy the /usr/lib/syslinux/menu.c32 file to the CD:
    cp -p /usr/lib/syslinux/menu.c32 isolinux
    
  7. Open the isolinux/isolinux.cfg file in your preferred text editor, and add the following line:
    mkisofs -o ./custom-boot.iso -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot \
      -boot-load-size 4 -boot-info-table -J -l -r -T -v -V "Custom RHEL Boot" .
    
  8. Customize any boot parameters and targets in isolinux.cfg as needed for CD booting.
  9. Burn the details to the CD to complete the procedure.

Procedure 9.2. PXE Boot

  1. Create a working directory for the boot image:
    mkdir -p temp pxe/pxelinux.cfg
    
  2. Mount the boot image to the temp directory:
    mount -o loop boot.iso temp
    
  3. Copy the required files for a PXE Boot device to the previously created directory:
    cp -aP temp/isolinux/* pxe/
    
  4. Unmount the temp directory and change the permissions on the cd directory to be readable and writable to the user:
    umount temp
    chmod -R u+rw pxe
    
  5. Change to the /pxe directory:
    cd ./pxe
    
  6. Copy the /usr/lib/syslinux/menu.c32 file to the /pxe directory:
    cp -p /usr/lib/syslinux/menu.c32 .
    
  7. Move the isolinux.cfg file to pxelinux.cfg/default:
    mv isolinux.cfg pxelinux.cfg/default
    
  8. Remove the temporary files:
    rm -f isolinux.bin TRANS.TBL
    
  9. Copy the /usr/lib/syslinux/pxelinux.0 file to the /pxe directory:
    cp -p /usr/lib/syslinux/pxelinux.0 .
    
  10. Open the pxelinux.cfg/default file in your preferred text editor, and customize any boot parameters and targets as needed for PXE booting.

Procedure 9.3. USB Boot Media

Warning

Be extremely careful when carrying out these command as root (required for most critical parts). These commands access device files and using them incorrectly could irrecoverably damage your system. The example below uses /dev/loop0 for mounting, make sure you use the correct device for your system. You can check which is the correct device using the losetup -f command.
  1. Create a working directory for the boot image:
    mkdir -p temp usb/extlinux
    
  2. Mount the boot image to the temp directory:
    mount -o loop boot.iso temp
    
  3. Copy the required files for a USB Media Boot device to the previously created directory:
    cp -aP temp/isolinux/* usb/extlinux/
    
  4. Unmount the temp directory and change the permissions on the cd directory to be readable and writable to the user:
    umount temp
    chmod -R u+rw usb
    
  5. Change to the /usb directory:
    cd ./usb
    
  6. Copy the /usr/lib/syslinux/menu.c32 file to the extlinux/ directory:
    cp -p /usr/lib/syslinux/menu.c32 extlinux/
    
  7. Move the extlinux/isolinux.cfg file to extlinux/extlinux.conf:
    mv extlinux/isolinux.cfg extlinux/extlinux.conf
    
  8. Remove the temporary files:
    rm -f extlinux/isolinux.bin extlinux/TRANS.TBL
    
  9. Convert the custom-boot.img file and copy it:
    dd if=/dev/zero of=./custom-boot.img bs=1024 count=30000
    
  10. Discover the correct mounting location for the loopback device:
    losetup -f
    /dev/loop0
    
    Set up the loopback device with the boot image:
    losetup /dev/loop0 ./custom-boot.img
    
  11. Open the fdisk utility:
    fdisk /dev/loop0
    
    Create one primary bootable partition on the device. This can be done by using the following key press combination: n p 1 Enter Enter a 1 p w
  12. Copy the master boot record (MBR) to the loopback device:
    dd if=/usr/lib/syslinux/mbr.bin of=/dev/loop0
    
  13. Add partition maps to the loopback device:
    kpartx -av /dev/loop0
    
  14. Create the file system:
    mkfs.ext2 -m 0 -L "Custom RHEL Boot" /dev/mapper/loop0p1
    
  15. Mount the device:
    mount /dev/mapper/loop0p1 temp
    
  16. Delete temporary files:
    rm -rf temp/lost+found
    
  17. Copy the extlinux/ directory to a temporary location:
    cp -a extlinux/* temp/
    
  18. Install the bootloader in the temporary location:
    extlinux temp
    
  19. Unmount the temporary location:
    umount temp
    
  20. Delete the partition maps on the loopback device:
    kpartx -dv /dev/loop0
    
  21. Delete the loopback device:
    losetup -d /dev/loop0
    
    Synchronize the file system changes:
    sync
    
  22. Open the extlinux.conf file in your preferred text editor, and customize any boot parameters and targets as needed for USB booting.
  23. Transfer the image to a USB device to complete the procedure. Insert the device, and run the dmesg command to check the mounting location. In this example, it is /dev/sdb.
    Unmount the USB device:
    umount /dev/sdb
    
    Copy the image to the USB device:
    dd if=./custom-boot.img of=/dev/sdb