Chapter 15. Preparing to install from the network using PXE

Steps

1. Export the installation ISO image or the installation tree to an NFS, HTTPS, HTTP, or FTP server.
2. Configure the HTTP or TFTP server and DHCP server, and start the HTTP or TFTP service on the server.
3. Boot the client and start the installation.

Procedure

1. Install the DHCP server:

   yum install dhcp-server

2. Set up a DHCPv4 server. Enter the following configuration in the /etc/dhcp/dhcpd.conf file. Replace the addresses to match your network card.

   option architecture-type code 93 = unsigned integer 16;
   
   subnet 192.168.124.0 netmask 255.255.255.0 {
     option routers 192.168.124.1;
     option domain-name-servers 192.168.124.1;
     range 192.168.124.100 192.168.124.200;
     class "pxeclients" {
       match if substring (option vendor-class-identifier, 0, 9) = "PXEClient";
       next-server 192.168.124.2;
             if option architecture-type = 00:07 {
               filename "redhat/EFI/BOOT/BOOTX64.EFI";
             }
             else {
               filename "pxelinux/pxelinux.0";
             }
     }
     class "httpclients" {
       match if substring (option vendor-class-identifier, 0, 10) = "HTTPClient";
       option vendor-class-identifier "HTTPClient";
       filename "http://192.168.124.2/redhat/EFI/BOOT/BOOTX64.EFI";
     }
   }

3. Start the DHCPv4 service:

   # systemctl enable --now dhcpd

Procedure

1. Install the DHCP server:

   yum install dhcp-server

2. Set up a DHCPv6 server. Enter the following configuration in the /etc/dhcp/dhcpd6.conf file. Replace the addresses to match your network card.

   option dhcp6.bootfile-url code 59 = string;
   option dhcp6.vendor-class code 16 = {integer 32, integer 16, string};
   
   subnet6 fd33:eb1b:9b36::/64 {
           range6 fd33:eb1b:9b36::64 fd33:eb1b:9b36::c8;
   
           class "PXEClient" {
                   match substring (option dhcp6.vendor-class, 6, 9);
           }
   
           subclass "PXEClient" "PXEClient" {
                   option dhcp6.bootfile-url "tftp://[fd33:eb1b:9b36::2]/redhat/EFI/BOOT/BOOTX64.EFI";
           }
   
           class "HTTPClient" {
                   match substring (option dhcp6.vendor-class, 6, 10);
           }
   
           subclass "HTTPClient" "HTTPClient" {
                   option dhcp6.bootfile-url "http://[fd33:eb1b:9b36::2]/redhat/EFI/BOOT/BOOTX64.EFI";
                   option dhcp6.vendor-class 0 10 "HTTPClient";
           }
   }

3. Start the DHCPv6 service:

   # systemctl enable --now dhcpd6

4. If DHCPv6 packets are dropped by the RP filter in the firewall, check its log. If the log contains the rpfilter_DROP entry, disable the filter using the following configuration in the /etc/firewalld/firewalld.conf file:

   IPv6_rpfilter=no

Procedure

1. As root, install the following package.

   # yum install tftp-server

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

   # firewall-cmd --add-service=tftp

   Note

   • This command enables temporary access until the next server reboot. To enable permanent access, add the --permanent option to the command.
   • Depending on the location of the installation ISO file, you might have to allow incoming connections for HTTP or other services.

3. Access the pxelinux.0 file from the SYSLINUX package in the DVD ISO image file, where my_local_directory is the name of the directory that you create:

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

   # cp -pr /mount_point/BaseOS/Packages/syslinux-tftpboot-version-architecture.rpm /my_local_directory

   # umount /mount_point

4. Extract the package:

   # rpm2cpio syslinux-tftpboot-version-architecture.rpm | cpio -dimv

5. Create a pxelinux/ directory in tftpboot/ and copy all the files from the directory into the pxelinux/ directory:

   # mkdir /var/lib/tftpboot/pxelinux

   # cp /my_local_directory/tftpboot/* /var/lib/tftpboot/pxelinux

6. Create the directory pxelinux.cfg/ in the pxelinux/ directory:

   # mkdir /var/lib/tftpboot/pxelinux/pxelinux.cfg

7. Create a configuration file named default and add it to the pxelinux.cfg/ directory as shown in the following example:

   default vesamenu.c32
   prompt 1
   timeout 600
   
   display boot.msg
   
   label linux
     menu label ^Install system
     menu default
     kernel images/RHEL-8/vmlinuz
     append initrd=images/RHEL-8/initrd.img ip=dhcp inst.repo=http://192.168.124.2/RHEL-8/x86_64/iso-contents-root/
   label vesa
     menu label Install system with ^basic video driver
     kernel images/RHEL-8/vmlinuz
     append initrd=images/RHEL-8/initrd.img ip=dhcp inst.xdriver=vesa nomodeset inst.repo=http://192.168.124.2/RHEL-8/x86_64/iso-contents-root/
   label rescue
     menu label ^Rescue installed system
     kernel images/RHEL-8/vmlinuz
     append initrd=images/RHEL-8/initrd.img inst.rescue
     inst.repo=http:///192.168.124.2/RHEL-8/x86_64/iso-contents-root/
   label local
     menu label Boot from ^local drive
     localboot 0xffff

   Note

   • 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 RHEL8 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.

8. 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/pxelinux/images/RHEL-8/:

   # mkdir -p /var/lib/tftpboot/pxelinux/images/RHEL-8/
   # cp /path_to_x86_64_images/pxeboot/{vmlinuz,initrd.img} /var/lib/tftpboot/pxelinux/images/RHEL-8/

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 when prompted to specify a boot source, and start the network installation.

Procedure

1. As root, install the following package.

   # yum install tftp-server

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

   # firewall-cmd --add-service=tftp

   Note

   • This command enables temporary access until the next server reboot. To enable permanent access, add the --permanent option to the command.
   • Depending on the location of the installation ISO file, you might have to allow incoming connections for HTTP or other services.

3. 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

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

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

5. Fix the permissions of the copied files:

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

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

   set timeout=60
   menuentry 'RHEL 8' {
     linuxefi images/RHEL-8/vmlinuz ip=dhcp inst.repo=http://192.168.124.2/RHEL-8/x86_64/iso-contents-root/
     initrdefi images/RHEL-8/initrd.img
   }

   Note

   • 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 RHEL8 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.

7. 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-8/:

   # mkdir -p /var/lib/tftpboot/images/RHEL-8/
   # cp /path_to_x86_64_images/pxeboot/{vmlinuz,initrd.img} /var/lib/tftpboot/images/RHEL-8/

8. 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 when prompted to specify a boot source, and start the network installation.

Procedure

1. As root, install the following packages:

   # yum install tftp-server dhcp-server

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

   # firewall-cmd --add-service=tftp

   Note

   • This command enables temporary access until the next server reboot. To enable permanent access, add the --permanent option to the command.
   • Depending on the location of the installation ISO file, you might have to allow incoming connections for HTTP or other services.

3. Create a GRUB2 network boot directory inside the TFTP root:

   # grub2-mknetdir --net-directory=/var/lib/tftpboot
   Netboot directory for powerpc-ieee1275 created. Configure your DHCP server to point to /boot/grub2/powerpc-ieee1275/core.elf

   Note

   The command output informs you of the file name that needs to be configured in your DHCP configuration, described in this procedure.

   1. If the PXE server runs on an x86 machine, the grub2-ppc64-modules must be installed before creating a GRUB2 network boot directory inside the tftp root:

      # yum install grub2-ppc64-modules

4. Create a GRUB2 configuration file: /var/lib/tftpboot/boot/grub2/grub.cfg as shown in the following example:

   set default=0
   set timeout=5
   
   echo -e "\nWelcome to the Red Hat Enterprise Linux 8 installer!\n\n"
   
   menuentry 'Red Hat Enterprise Linux 8' {
     linux grub2-ppc64/vmlinuz ro ip=dhcp inst.repo=http://192.168.124.2/RHEL-8/x86_64/iso-contents-root/
     initrd grub2-ppc64/initrd.img
   }

   Note

   • 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 RHEL8 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.

5. Mount the DVD ISO image using the command:

   # mount -t iso9660 /path_to_image/name_of_iso/ /mount_point -o loop,ro

6. Create a directory and copy the initrd.img and vmlinuz files from DVD ISO image into it, for example:

   # cp /mount_point/ppc/ppc64/{initrd.img,vmlinuz} /var/lib/tftpboot/grub2-ppc64/

7. Configure your DHCP server to use the boot images packaged with GRUB2 as shown in the following example. Note that if you already have a DHCP server configured, then perform this step on the DHCP server.

   TODO: This DHCP configuration must be different from the other, regular BIOS and UEFI entries, right?

   subnet 192.168.0.1 netmask 255.255.255.0 {
     allow bootp;
     option routers 192.168.0.5;
     group { #BOOTP POWER clients
       filename "boot/grub2/powerpc-ieee1275/core.elf";
       host client1 {
       hardware ethernet 01:23:45:67:89:ab;
       fixed-address 192.168.0.112;
       }
     }
   }

8. Adjust the sample parameters subnet, netmask, routers, fixed-address and hardware ethernet to fit your network configuration. Note the file name parameter; this is the file name that was outputted by the grub2-mknetdir command earlier in this procedure.

9. On the DHCP server, start and enable the dhcpd service. If you have configured a DHCP server on the localhost, then start and enable the dhcpd service on the localhost.

   # systemctl enable --now dhcpd

10. 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 when prompted to specify a boot source, and start the network installation.