Chapter 8. Booting hosts with the discovery image

Procedure

1. On the administration host, insert a USB drive into a USB port.

2. Copy the ISO image to the USB drive, for example:

   # dd if=<path_to_iso> of=<path_to_usb> status=progress

   where:

   <path_to_iso>

   is the relative path to the downloaded discovery ISO file, for example, discovery.iso.

   <path_to_usb>

   is the location of the connected USB drive, for example, /dev/sdb.

   After the ISO is copied to the USB drive, you can use the USB drive to install the Assisted Installer agent on the cluster host.

Procedure

1. Insert the RHCOS discovery ISO USB drive into the target host.
2. Configure the boot drive order in the server firmware settings to boot from the attached discovery ISO, and then reboot the server.

3. Wait for the host to boot up.

   1. For web console installations, on the administration host, return to the browser. Wait for the host to appear in the list of discovered hosts.

   2. For API installations, refresh the token, check the enabled host count, and gather the host IDs:

      $ source refresh-token

      $ curl -s -X GET "https://api.openshift.com/api/assisted-install/v2/clusters/$CLUSTER_ID" \
      --header "Content-Type: application/json" \
        -H "Authorization: Bearer $API_TOKEN" \
      | jq '.enabled_host_count'

      $ curl -s -X GET "https://api.openshift.com/api/assisted-install/v2/clusters/$CLUSTER_ID" \
      --header "Content-Type: application/json" \
        -H "Authorization: Bearer $API_TOKEN" \
      | jq '.host_networks[].host_ids'

      Example output

      [
        "1062663e-7989-8b2d-7fbb-e6f4d5bb28e5"
      ]

Procedure

1. Copy the ISO file to an HTTP server accessible in your network.

2. Boot the host from the hosted ISO file, for example:

   1. Call the redfish API to set the hosted ISO as the VirtualMedia boot media by running the following command:

      $ curl -k -u <bmc_username>:<bmc_password> \
      -d '{"Image":"<hosted_iso_file>", "Inserted": true}' \
      -H "Content-Type: application/json" \
      -X POST <host_bmc_address>/redfish/v1/Managers/iDRAC.Embedded.1/VirtualMedia/CD/Actions/VirtualMedia.InsertMedia

      Where:

      <bmc_username>:<bmc_password>

      Is the username and password for the target host BMC.

      <hosted_iso_file>

      Is the URL for the hosted installation ISO, for example: https://example.com/rhcos-live-minimal.iso. The ISO must be accessible from the target host machine.

      <host_bmc_address>

      Is the BMC IP address of the target host machine.

   2. Set the host to boot from the VirtualMedia device by running the following command:

      $ curl -k -u <bmc_username>:<bmc_password> \
      -X PATCH -H 'Content-Type: application/json' \
      -d '{"Boot": {"BootSourceOverrideTarget": "Cd", "BootSourceOverrideMode": "UEFI", "BootSourceOverrideEnabled": "Once"}}' \
      <host_bmc_address>/redfish/v1/Systems/System.Embedded.1

   3. Reboot the host:

      $ curl -k -u <bmc_username>:<bmc_password> \
      -d '{"ResetType": "ForceRestart"}' \
      -H 'Content-type: application/json' \
      -X POST <host_bmc_address>/redfish/v1/Systems/System.Embedded.1/Actions/ComputerSystem.Reset

   4. Optional: If the host is powered off, you can boot it using the {"ResetType": "On"} switch. Run the following command:

      $ curl -k -u <bmc_username>:<bmc_password> \
      -d '{"ResetType": "On"}' -H 'Content-type: application/json' \
      -X POST <host_bmc_address>/redfish/v1/Systems/System.Embedded.1/Actions/ComputerSystem.Reset

Procedure

1. Download the iPXE script directly from the web console, or get the iPXE script from the Assisted Installer by running the following command:

   $ curl \
     --silent \
     --header "Authorization: Bearer $API_TOKEN" \
     https://api.openshift.com/api/assisted-install/v2/infra-envs/$INFRA_ENV_ID/downloads/files?file_name=ipxe-script > ipxe-script

   Example

   #!ipxe
   initrd --name initrd http://api.openshift.com/api/assisted-images/images/<infra_env_id>/pxe-initrd?arch=x86_64&image_token=<token_string>&version=4.10
   kernel http://api.openshift.com/api/assisted-images/boot-artifacts/kernel?arch=x86_64&version=4.10 initrd=initrd coreos.live.rootfs_url=http://api.openshift.com/api/assisted-images/boot-artifacts/rootfs?arch=x86_64&version=4.10 random.trust_cpu=on rd.luks.options=discard ignition.firstboot ignition.platform.id=metal console=tty1 console=ttyS1,115200n8 coreos.inst.persistent-kargs="console=tty1 console=ttyS1,115200n8"
   boot

2. Download the required artifacts by extracting URLs from the ipxe-script:

   1. Download the initial RAM disk by running the following command:

      $ awk '/^initrd /{print $NF}' ipxe-script \
      | xargs curl -o initrd.img -L

   2. Download the Linux kernel by running the following command:

      $ awk '/^kernel /{print $2}' ipxe-script | xargs curl -o kernel -L

   3. Download the root filesystem by running the following command:

      $ grep ^kernel ipxe-script | xargs n1| grep ^coreos.live.rootfs_url | cut -d = -f 2 | xargs curl -o rootfs.img -L

3. Change the URLs to the different artifacts in the ipxe-script to match your local HTTP server. For example:

   #!ipxe
   set webserver http://192.168.0.1
   initrd --name initrd $webserver/initrd.img
   kernel $webserver/kernel initrd=initrd coreos.live.rootfs_url=$webserver/rootfs.img random.trust_cpu=on rd.luks.options=discard ignition.firstboot ignition.platform.id=metal console=tty1 console=ttyS1,115200n8 coreos.inst.persistent-kargs="console=tty1 console=ttyS1,115200n8"
   boot

4. Optional: When installing with RHEL KVM on IBM Z® you must boot the host by specifying additional kernel arguments:

   random.trust_cpu=on rd.luks.options=discard ignition.firstboot ignition.platform.id=metal console=tty1 console=ttyS1,115200n8 coreos.inst.persistent-kargs="console=tty1 console=ttyS1,115200n8

   Note

   When you install with iPXE on RHEL KVM, the VMs on the VM host might not start on the first boot. You must start them manually.

5. Optional: When installing on IBM Power® you must download the initramfs, kernel, and root images as follows:

   1. Copy the initrd.img and kernel.img images to the /var/lib/tftpboot/rhcos PXE directory.
   2. Copy the rootfs.img to the /var/www/html/install HTTPD directory.

   3. Add the following entry to the /var/lib/tftpboot/boot/grub2/grub.cfg directory:

      if [ ${net_default_mac} == fa:1d:67:35:13:20 ]; then
      default=0
      fallback=1
      timeout=1
      menuentry "CoreOS (BIOS)" {
      echo "Loading kernel"
      linux "/rhcos/kernel.img" ip=dhcp rd.neednet=1 ignition.platform.id=metal ignition.firstboot coreos.live.rootfs_url=http://9.114.98.8:8000/install/rootfs.img
      echo "Loading initrd"
      initrd "/rhcos/initrd.img"
      }
      fi