Chapter 7. Booting the installation
After you have created bootable media you are ready to boot the Red Hat Enterprise Linux installation.
7.1. Boot menu
The Red Hat Enterprise Linux boot menu is displayed using GRand Unified Bootloader version 2 (GRUB2) when your system has completed loading the boot media.
Figure 7.1. Red Hat Enterprise Linux boot menu
The boot menu provides several options in addition to launching the installation program. If you do not make a selection within 60 seconds, the default boot option (highlighted in white) is run. To select a different option, use the arrow keys on your keyboard to make your selection and press the Enter key.
You can customize boot options for a particular menu entry:
-
On BIOS-based systems: Press the Tab key and add custom boot options to the command line. You can also access the
boot:prompt by pressing the Esc key but no required boot options are preset. In this scenario, you must always specify the Linux option before using any other boot options. - On UEFI-based systems: Press the e key and add custom boot options to the command line. When ready press Ctrl+X to boot the modified option.
Table 7.1. Boot menu options
| Boot menu option | Description |
|---|---|
| Install Red Hat Enterprise Linux 8 | Use this option to install Red Hat Enterprise Linux using the graphical installation program. For more information, see Chapter 8, Installing RHEL using an ISO image from the Customer Portal |
| Test this media & install Red Hat Enterprise Linux 8 | Use this option to check the integrity of the installation media. For more information, see Section F.4, “Verifying boot media” |
| Troubleshooting > | Use this option to resolve various installation issues. Press Enter to display its contents. |
Table 7.2. Troubleshooting options
| Troubleshooting option | Description |
|---|---|
| Troubleshooting > Install Red Hat Enterprise Linux 8 in basic graphics mode | Use this option to install Red Hat Enterprise Linux in graphical mode even if the installation program is unable to load the correct driver for your video card. If your screen is distorted when using the Install Red Hat Enterprise Linux 8 option, restart your system and use this option. For more information, see Section F.7, “Display settings and device drivers” |
| Troubleshooting > Rescue a Red Hat Enterprise Linux system | Use this option to repair any issues that prevent you from booting. For more information, see Section G.10, “Using rescue mode” |
| Troubleshooting > Run a memory test | Use this option to run a memory test on your system. Press Enter to display its contents. For more information, see see Section F.3, “Detecting memory faults using the Memtest86 application” |
| Troubleshooting > Boot from local drive | Use this option to boot the system from the first installed disk. If you booted this disk accidentally, use this option to boot from the hard disk immediately without starting the installation program. |
7.2. Types of boot options
There are two types of boot options; those with an equals "=" sign, and those without an equals "=" sign. Boot options are appended to the boot command line and multiple options must be separated by a single space. Boot options that are specific to the installation program always start with inst.
- Options with an equals "=" sign
-
You must specify a value for boot options that use the
=symbol. For example, theinst.vncpassword=option must contain a value, in this case, a password. The correct syntax for this example isinst.vncpassword=password. - Options without an equals "=" sign
-
This boot option does not accept any values or parameters. For example, the
rd.live.checkoption forces the installation program to verify the installation media before starting the installation. If this boot option is present, the verification is performed; if the boot option is not present, the verification is skipped.
7.3. Editing boot options
This section contains information about the different ways that you can edit boot options from the boot menu. The boot menu opens after you boot the installation media.
Editing the boot: prompt in BIOS
When using the boot: prompt, the first option must always specify the installation program image file that you want to load. In most cases, you can specify the image using the keyword. You can specify additional options according to your requirements.
Prerequisites
- You have created bootable installation media (USB, CD or DVD).
- You have booted the installation from the media, and the installation boot menu is open.
Procedure
- With the boot menu open, press the Esc key on your keyboard.
-
The
boot:prompt is now accessible. - Press the Tab key on your keyboard to display the help commands.
-
Press the Enter key on your keyboard to start the installation with your options. To return from the
boot:prompt to the boot menu, restart the system and boot from the installation media again.
The boot: prompt also accepts dracut kernel options. A list of options is available in the dracut.cmdline(7) man page.
Editing the > prompt
You can use the > prompt to edit predefined boot options. For example, select Test this media and install Red Hat Enterprise Linux 8.1 from the boot menu to display a full set of options.
This procedure is for BIOS-based AMD64 and Intel 64 systems.
Prerequisites
- You have created bootable installation media (USB, CD or DVD).
- You have booted the installation from the media, and the installation boot menu is open.
Procedure
-
From the boot menu, select an option and press the Tab key on your keyboard. The
>prompt is accessible and displays the available options. -
Append the options that you require to the
>prompt. - Press the Enter key on your keyboard to start the installation.
- Press the Esc key on your keyboard to cancel editing and return to the boot menu.
Editing the GRUB2 menu
The GRUB2 menu is available on UEFI-based AMD64, Intel 64, and 64-bit ARM systems.
Prerequisites
- You have created bootable installation media (USB, CD or DVD).
- You have booted the installation from the media, and the installation boot menu is open.
Procedure
- From the boot menu window, select the required option and press the e key on your keyboard.
-
Move the cursor to the kernel command line. On UEFI systems, the kernel command line starts with
linuxefi. -
Move the cursor to the end of the
linuxefikernel command line. -
Edit the parameters as required. For example, to configure one or more network interfaces, add the
ip=parameter at the end of thelinuxefikernel command line, followed by the required value. - When you finish editing, press Ctrl+X on your keyboard to start the installation using the specified options.
7.4. Booting the installation from a USB, CD, or DVD
Follow the steps in this procedure to boot the Red Hat Enterprise Linux installation using a USB, CD, or DVD. The following steps are generic. Consult your hardware manufacturer’s documentation for specific instructions.
Prerequisite
You have created bootable installation media (USB, CD or DVD). See Creating a bootable DVD or CD for more information.
Procedure
- Power off the system to which you are installing Red Hat Enterprise Linux.
- Disconnect any drives from the system.
- Power on the system.
- Insert the bootable installation media (USB, DVD, or CD).
- Power off the system but do not remove the boot media.
Power on the system.
NoteYou might need to press a specific key or combination of keys to boot from the media or configure the Basic Input/Output System (BIOS) of your system to boot from the media. For more information, see the documentation that came with your system.
- The Red Hat Enterprise Linux boot window opens and displays information about a variety of available boot options.
Use the arrow keys on your keyboard to select the boot option that you require, and press Enter to select the boot option. The Welcome to Red Hat Enterprise Linux window opens and you can install Red Hat Enterprise Linux using the graphical user interface.
NoteThe installation program automatically begins if no action is performed in the boot window within 60 seconds.
Optionally, edit the available boot options:
- UEFI-based systems: Press E to enter edit mode. Change the predefined command line to add or remove boot options. Press Enter to confirm your choice.
- BIOS-based systems: Press the Tab key on your keyboard to enter edit mode. Change the predefined command line to add or remove boot options. Press Enter to confirm your choice.
Additional Resources
- For more information about installing Red Hat Enterprise Linux using the Graphical User Interface, see Chapter 10, Customizing your installation.
- For more information about the list of available boot options you can use on the boot command line, see Appendix C, Boot options reference.
7.5. Booting the installation from a network using PXE
When installing Red Hat Enterprise Linux on a large number of systems simultaneously, the best approach is to boot from a PXE server and install from a source in a shared network location. Follow the steps in this procedure to boot the Red Hat Enterprise Linux installation from a network using PXE.
To boot the installation process from a network using PXE, you must use a physical network connection, for example, Ethernet. You cannot boot the installation process with a wireless connection.
Prerequisites
- You have configured a TFTP server, and there is a network interface in your system that supports PXE. See Additional resources for more information.
- You have configured your system to boot from the network interface. This option is in the BIOS, and can be labeled Network Boot or Boot Services.
- You have verified that the BIOS is configured to boot from the specified network interface. Some BIOS systems specify the network interface as a possible boot device, but do not support the PXE standard. See your hardware’s documentation for more information. When you have properly enabled PXE booting, the system can boot the Red Hat Enterprise Linux installation program without any other media.
Procedure
- Verify that the network cable is attached. The link indicator light on the network socket should be lit, even if the computer is not switched on.
Switch on the system.
Depending on your hardware, some network setup and diagnostic information can be displayed before your system connects to a PXE server. When connected, a menu is displayed according to the PXE server configuration.
Press the number key that corresponds to the option that you require.
NoteIn some instances, boot options are not displayed. If this occurs, press the Enter key on your keyboard or wait until the boot window opens.
The Red Hat Enterprise Linux boot window opens and displays information about a variety of available boot options.
Use the arrow keys on your keyboard to select the boot option that you require, and press Enter to select the boot option. The Welcome to Red Hat Enterprise Linux window opens and you can install Red Hat Enterprise Linux using the graphical user interface.
NoteThe installation program automatically begins if no action is performed in the boot window within 60 seconds.
Optionally, edit the available boot options:
- UEFI-based systems: Press E to enter edit mode. Change the predefined command line to add or remove boot options. Press Enter to confirm your choice.
- BIOS-based systems: Press the Tab key on your keyboard to enter edit mode. Change the predefined command line to add or remove boot options. Press Enter to confirm your choice.
Additional Resources
- For information about installing Red Hat Enterprise Linux using the Graphical User Interface, see Chapter 10, Customizing your installation.
- For information about how to prepare to install Red Hat Enterprise Linux from the network using PXE, see the Performing an advanced RHEL installation document.
- For more information about the list of available boot options you can use on the boot command line, see Appendix C, Boot options reference.