7.5. Configuring a TFTP server for UEFI-based clients

Procedure

1. As root, install the following package.

   # dnf install tftp-server

2. Allow incoming connections to the tftp service in the firewall:

   # firewall-cmd --add-service=tftp

   This command enables temporary access until the next server reboot.

3. Optional: To enable permanent access, repeat the previous command together with the --permanent option.

   Depending on the location of the installation ISO file, you might have to allow incoming connections for HTTP or other services.

4. Access the EFI boot image files from the DVD ISO image:

   # mount -t iso9660 /path_to_image/name_of_image.iso /mount_point -o loop,ro

5. Copy the EFI boot images from the DVD ISO image:

   # mkdir /var/lib/tftpboot/redhat
   # cp -r /mount_point/EFI /var/lib/tftpboot/redhat/

6. Create a subdirectory to store the boot image files in the /var/lib/tftpboot/ directory, and copy the boot image files to the directory. In this example, the directory is /var/lib/tftpboot/images/RHEL-10/:

   # mkdir -p /var/lib/tftpboot/images/RHEL-10/
   # cp /mount_point/images/pxeboot/{vmlinuz,initrd.img} /var/lib/tftpboot/images/RHEL-10/
   # umount /mount_point

7. Fix the permissions of the copied files:

   # chmod -R 755 /var/lib/tftpboot/redhat/

8. Replace the content of /var/lib/tftpboot/redhat/EFI/BOOT/grub.cfg with the following example:

   set default="1"
   set timeout=60
   
   function load_video {
     insmod efi_gop
     insmod efi_uga
     insmod video_bochs
     insmod video_cirrus
     insmod all_video
   }
   
   load_video
   set gfxpayload=keep
   
   menuentry 'Install Red Hat Enterprise Linux 10.0' --class fedora --class gnu-linux --class gnu --class os {
       	linuxefi /images/RHEL-10/vmlinuz inst.repo=http://192.168.124.2/redhat/iso quiet
       	initrdefi /images/RHEL-10/initrd.img
   }
   submenu 'Troubleshooting -->' {
       	menuentry 'Install Red Hat Enterprise Linux 10.0 in text mode' --class fedora --class gnu-linux --class gnu --class os {
               	linuxefi /images/RHEL-10/vmlinuz inst.repo=http://192.168.124.2/redhat/iso inst.text quiet
               	initrdefi /images/RHEL-10/initrd.img
       	}
       	menuentry 'Rescue a Red Hat Enterprise Linux system' --class fedora --class gnu-linux --class gnu --class os {
               	linuxefi /images/RHEL-10/vmlinuz inst.stage2=http://192.168.124.2/redhat/iso inst.rescue quiet
               	initrdefi /images/RHEL-10/initrd.img
       	}
   }

   • The installation program cannot boot without its runtime image. Use the inst.stage2 boot option to specify location of the image. Alternatively, you can use the inst.repo= option to specify the image as well as the installation source.
   • The installation source location used with inst.repo must contain a valid .treeinfo file.
   • When you select the RHEL10 installation DVD as the installation source, the .treeinfo file points to the BaseOS and the AppStream repositories. You can use a single inst.repo option to load both repositories.

9. Start and enable the tftp.socket service:

   # systemctl enable --now tftp.socket

   The PXE boot server is now ready to serve PXE clients. You can start the client, which is the system to which you are installing Red Hat Enterprise Linux. Select PXE Boot or Network Boot when prompted to specify a boot source, and start the network installation.