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Installing RHEL on the provisioner node

With the configuration of the prerequisites complete, the next step is to install RHEL 8.x on the provisioner node. The installer uses the provisioner node as the orchestrator while installing the OpenShift Container Platform cluster. For the purposes of this document, installing RHEL on the provisioner node is out of scope. However, options include but are not limited to using a RHEL Satellite server, PXE, or installation media.

Preparing the provisioner node for OpenShift Container Platform installation

Perform the following steps to prepare the environment.

Procedure
  1. Log in to the provisioner node via ssh.

  2. Create a non-root user (kni) and provide that user with sudo privileges:

    # useradd kni
    # passwd kni
    # echo "kni ALL=(root) NOPASSWD:ALL" | tee -a /etc/sudoers.d/kni
    # chmod 0440 /etc/sudoers.d/kni
  3. Create an ssh key for the new user:

    # su - kni -c "ssh-keygen -t ed25519 -f /home/kni/.ssh/id_rsa -N ''"
  4. Log in as the new user on the provisioner node:

    # su - kni
  5. Use Red Hat Subscription Manager to register the provisioner node:

    $ sudo subscription-manager register --username=<user> --password=<pass> --auto-attach
    $ sudo subscription-manager repos --enable=rhel-8-for-x86_64-appstream-rpms --enable=rhel-8-for-x86_64-baseos-rpms

    For more information about Red Hat Subscription Manager, see Using and Configuring Red Hat Subscription Manager.

  6. Install the following packages:

    $ sudo dnf install -y libvirt qemu-kvm mkisofs python3-devel jq ipmitool
  7. Modify the user to add the libvirt group to the newly created user:

    $ sudo usermod --append --groups libvirt <user>
  8. Restart firewalld and enable the http service:

    $ sudo systemctl start firewalld
    $ sudo firewall-cmd --zone=public --add-service=http --permanent
    $ sudo firewall-cmd --reload
  9. Start and enable the libvirtd service:

    $ sudo systemctl enable libvirtd --now
  10. Create the default storage pool and start it:

    $ sudo virsh pool-define-as --name default --type dir --target /var/lib/libvirt/images
    $ sudo virsh pool-start default
    $ sudo virsh pool-autostart default
  11. Configure networking.

    You can also configure networking from the web console.

    Export the baremetal network NIC name:

    $ export PUB_CONN=<baremetal_nic_name>

    Configure the baremetal network:

    $ sudo nohup bash -c "
        nmcli con down \"$PUB_CONN\"
        nmcli con delete \"$PUB_CONN\"
        # RHEL 8.1 appends the word \"System\" in front of the connection, delete in case it exists
        nmcli con down \"System $PUB_CONN\"
        nmcli con delete \"System $PUB_CONN\"
        nmcli connection add ifname baremetal type bridge con-name baremetal
        nmcli con add type bridge-slave ifname \"$PUB_CONN\" master baremetal
        pkill dhclient;dhclient baremetal
    "

    If you are deploying with a provisioning network, export the provisioning network NIC name:

    $ export PROV_CONN=<prov_nic_name>

    If you are deploying with a provisioning network, configure the provisioning network:

    $ sudo nohup bash -c "
        nmcli con down \"$PROV_CONN\"
        nmcli con delete \"$PROV_CONN\"
        nmcli connection add ifname provisioning type bridge con-name provisioning
        nmcli con add type bridge-slave ifname \"$PROV_CONN\" master provisioning
        nmcli connection modify provisioning ipv6.addresses fd00:1101::1/64 ipv6.method manual
        nmcli con down provisioning
        nmcli con up provisioning
    "

    The ssh connection might disconnect after executing these steps.

    The IPv6 address can be any address as long as it is not routable via the baremetal network.

    Ensure that UEFI is enabled and UEFI PXE settings are set to the IPv6 protocol when using IPv6 addressing.

  12. Configure the IPv4 address on the provisioning network connection:

    $ nmcli connection modify provisioning ipv4.addresses 172.22.0.254/24 ipv4.method manual
  13. ssh back into the provisioner node (if required):

    # ssh kni@provisioner.<cluster-name>.<domain>
  14. Verify the connection bridges have been properly created:

    $ sudo nmcli con show
    NAME               UUID                                  TYPE      DEVICE
    baremetal          4d5133a5-8351-4bb9-bfd4-3af264801530  bridge    baremetal
    provisioning       43942805-017f-4d7d-a2c2-7cb3324482ed  bridge    provisioning
    virbr0             d9bca40f-eee1-410b-8879-a2d4bb0465e7  bridge    virbr0
    bridge-slave-eno1  76a8ed50-c7e5-4999-b4f6-6d9014dd0812  ethernet  eno1
    bridge-slave-eno2  f31c3353-54b7-48de-893a-02d2b34c4736  ethernet  eno2
  15. Create a pull-secret.txt file:

    $ vim pull-secret.txt

    In a web browser, navigate to Install OpenShift on Bare Metal with installer-provisioned infrastructure. Click Copy pull secret. Paste the contents into the pull-secret.txt file and save the contents in the kni user’s home directory.

Retrieving the OpenShift Container Platform installer

Use the stable-4.x version of the installer to deploy the generally available stable version of OpenShift Container Platform:

$ export VERSION=stable-4.10
export RELEASE_IMAGE=$(curl -s https://mirror.openshift.com/pub/openshift-v4/clients/ocp/$VERSION/release.txt | grep 'Pull From: quay.io' | awk -F ' ' '{print $3}')

Extracting the OpenShift Container Platform installer

After retrieving the installer, the next step is to extract it.

Procedure
  1. Set the environment variables:

    $ export cmd=openshift-baremetal-install
    $ export pullsecret_file=~/pull-secret.txt
    $ export extract_dir=$(pwd)
  2. Get the oc binary:

    $ curl -s https://mirror.openshift.com/pub/openshift-v4/clients/ocp/$VERSION/openshift-client-linux.tar.gz | tar zxvf - oc
  3. Extract the installer:

    $ sudo cp oc /usr/local/bin
    $ oc adm release extract --registry-config "${pullsecret_file}" --command=$cmd --to "${extract_dir}" ${RELEASE_IMAGE}
    $ sudo cp openshift-baremetal-install /usr/local/bin

(Optional) Creating an RHCOS images cache

To employ image caching, you must download the Red Hat Enterprise Linux CoreOS (RHCOS) image used by the bootstrap VM to provision the cluster nodes. Image caching is optional, but it is especially useful when running the installation program on a network with limited bandwidth.

The installation program no longer needs the clusterOSImage RHCOS image because the correct image is in the release payload.

If you are running the installation program on a network with limited bandwidth and the RHCOS images download takes more than 15 to 20 minutes, the installation program will timeout. Caching images on a web server will help in such scenarios.

Install a container that contains the images.

Procedure
  1. Install podman:

    $ sudo dnf install -y podman
  2. Open firewall port 8080 to be used for RHCOS image caching:

    $ sudo firewall-cmd --add-port=8080/tcp --zone=public --permanent
    $ sudo firewall-cmd --reload
  3. Create a directory to store the bootstraposimage:

    $ mkdir /home/kni/rhcos_image_cache
  4. Set the appropriate SELinux context for the newly created directory:

    $ sudo semanage fcontext -a -t httpd_sys_content_t "/home/kni/rhcos_image_cache(/.*)?"
    $ sudo restorecon -Rv /home/kni/rhcos_image_cache/
  5. Get the URI for the RHCOS image that the installation program will deploy on the bootstrap VM:

    $ export RHCOS_QEMU_URI=$(/usr/local/bin/openshift-baremetal-install coreos print-stream-json | jq -r --arg ARCH "$(arch)" '.architectures[$ARCH].artifacts.qemu.formats["qcow2.gz"].disk.location')
  6. Get the name of the image that the installation program will deploy on the bootstrap VM:

    $ export RHCOS_QEMU_NAME=${RHCOS_QEMU_URI##*/}
  7. Get the SHA hash for the RHCOS image that will be deployed on the bootstrap VM:

    $ export RHCOS_QEMU_UNCOMPRESSED_SHA256=$(/usr/local/bin/openshift-baremetal-install coreos print-stream-json | jq -r --arg ARCH "$(arch)" '.architectures[$ARCH].artifacts.qemu.formats["qcow2.gz"].disk["uncompressed-sha256"]')
  8. Download the image and place it in the /home/kni/rhcos_image_cache directory:

    $ curl -L ${RHCOS_QEMU_URI} -o /home/kni/rhcos_image_cache/${RHCOS_QEMU_NAME}
  9. Confirm SELinux type is of httpd_sys_content_t for the new file:

    $ ls -Z /home/kni/rhcos_image_cache
  10. Create the pod:

    $ podman run -d --name rhcos_image_cache \ (1)
    -v /home/kni/rhcos_image_cache:/var/www/html \
    -p 8080:8080/tcp \
    quay.io/centos7/httpd-24-centos7:latest
    1 Creates a caching webserver with the name rhcos_image_cache. This pod serves the bootstrapOSImage image in the install-config.yaml file for deployment.
  11. Generate the bootstrapOSImage configuration:

    $ export BAREMETAL_IP=$(ip addr show dev baremetal | awk '/inet /{print $2}' | cut -d"/" -f1)
    $ export BOOTSTRAP_OS_IMAGE="http://${BAREMETAL_IP}:8080/${RHCOS_QEMU_NAME}?sha256=${RHCOS_QEMU_UNCOMPRESSED_SHA256}"
    $ echo "    bootstrapOSImage=${BOOTSTRAP_OS_IMAGE}"
  12. Add the required configuration to the install-config.yaml file under platform.baremetal:

    platform:
      baremetal:
        bootstrapOSImage: <bootstrap_os_image>  (1)
    
    1 Replace <bootstrap_os_image> with the value of $BOOTSTRAP_OS_IMAGE.

    See the "Configuring the install-config.yaml file" section for additional details.

Configuring the install-config.yaml file

Configuring the install-config.yaml file

The install-config.yaml file requires some additional details. Most of the information teaches the installation program and the resulting cluster enough about the available hardware that it is able to fully manage it.

The installation program no longer needs the clusterOSImage RHCOS image because the correct image is in the release payload.

  1. Configure install-config.yaml. Change the appropriate variables to match the environment, including pullSecret and sshKey.

    apiVersion: v1
    baseDomain: <domain>
    metadata:
      name: <cluster-name>
    networking:
      machineNetwork:
      - cidr: <public-cidr>
      networkType: OVNKubernetes
    compute:
    - name: worker
      replicas: 2 (1)
    controlPlane:
      name: master
      replicas: 3
      platform:
        baremetal: {}
    platform:
      baremetal:
        apiVIP: <api-ip>
        ingressVIP: <wildcard-ip>
        provisioningNetworkCIDR: <CIDR>
        hosts:
          - name: openshift-master-0
            role: master
            bmc:
              address: ipmi://<out-of-band-ip> (2)
              username: <user>
              password: <password>
            bootMACAddress: <NIC1-mac-address>
            rootDeviceHints:
             deviceName: "/dev/disk/by-id/<disk_id>" (3)
          - name: <openshift-master-1>
            role: master
            bmc:
              address: ipmi://<out-of-band-ip> (2)
              username: <user>
              password: <password>
            bootMACAddress: <NIC1-mac-address>
            rootDeviceHints:
             deviceName: "/dev/disk/by-id/<disk_id>" (3)
          - name: <openshift-master-2>
            role: master
            bmc:
              address: ipmi://<out-of-band-ip> (2)
              username: <user>
              password: <password>
            bootMACAddress: <NIC1-mac-address>
            rootDeviceHints:
             deviceName: "/dev/disk/by-id/<disk_id>" (3)
          - name: <openshift-worker-0>
            role: worker
            bmc:
              address: ipmi://<out-of-band-ip> (2)
              username: <user>
              password: <password>
            bootMACAddress: <NIC1-mac-address>
          - name: <openshift-worker-1>
            role: worker
            bmc:
              address: ipmi://<out-of-band-ip>
              username: <user>
              password: <password>
            bootMACAddress: <NIC1-mac-address>
            rootDeviceHints:
             deviceName: "/dev/disk/by-id/<disk_id>" (3)
    pullSecret: '<pull_secret>'
    sshKey: '<ssh_pub_key>'
    1 Scale the worker machines based on the number of worker nodes that are part of the OpenShift Container Platform cluster. Valid options for the replicas value are 0 and integers greater than or equal to 2. Set the number of replicas to 0 to deploy a three-node cluster, which contains only three control plane machines. A three-node cluster is a smaller, more resource-efficient cluster that can be used for testing, development, and production. You cannot install the cluster with only one worker.
    2 See the BMC addressing sections for more options.
    3 Set the path to the installation disk drive, for example, /dev/disk/by-id/wwn-0x64cd98f04fde100024684cf3034da5c2.
  2. Create a directory to store cluster configs:

    $ mkdir ~/clusterconfigs
  3. Copy the install-config.yaml file to the new directory:

    $ cp install-config.yaml ~/clusterconfigs
  4. Ensure all bare metal nodes are powered off prior to installing the OpenShift Container Platform cluster:

    $ ipmitool -I lanplus -U <user> -P <password> -H <management-server-ip> power off
  5. Remove old bootstrap resources if any are left over from a previous deployment attempt:

    for i in $(sudo virsh list | tail -n +3 | grep bootstrap | awk {'print $2'});
    do
      sudo virsh destroy $i;
      sudo virsh undefine $i;
      sudo virsh vol-delete $i --pool $i;
      sudo virsh vol-delete $i.ign --pool $i;
      sudo virsh pool-destroy $i;
      sudo virsh pool-undefine $i;
    done

Additional install-config parameters

See the following tables for the required parameters, the hosts parameter, and the bmc parameter for the install-config.yaml file.

Table 1. Required parameters
Parameters Default Description

baseDomain

The domain name for the cluster. For example, example.com.

bootMode

UEFI

The boot mode for a node. Options are legacy, UEFI, and UEFISecureBoot. If bootMode is not set, Ironic sets it while inspecting the node.

sshKey

The sshKey configuration setting contains the key in the ~/.ssh/id_rsa.pub file required to access the control plane nodes and worker nodes. Typically, this key is from the provisioner node.

pullSecret

The pullSecret configuration setting contains a copy of the pull secret downloaded from the Install OpenShift on Bare Metal page when preparing the provisioner node.

metadata:
    name:

The name to be given to the OpenShift Container Platform cluster. For example, openshift.

networking:
    machineNetwork:
    - cidr:

The public CIDR (Classless Inter-Domain Routing) of the external network. For example, 10.0.0.0/24.

compute:
  - name: worker

The OpenShift Container Platform cluster requires a name be provided for worker (or compute) nodes even if there are zero nodes.

compute:
    replicas: 2

Replicas sets the number of worker (or compute) nodes in the OpenShift Container Platform cluster.

controlPlane:
    name: master

The OpenShift Container Platform cluster requires a name for control plane (master) nodes.

controlPlane:
    replicas: 3

Replicas sets the number of control plane (master) nodes included as part of the OpenShift Container Platform cluster.

provisioningNetworkInterface

The name of the network interface on nodes connected to the provisioning network. For OpenShift Container Platform 4.9 and later releases, use the bootMACAddress configuration setting to enable Ironic to identify the IP address of the NIC instead of using the provisioningNetworkInterface configuration setting to identify the name of the NIC.

defaultMachinePlatform

The default configuration used for machine pools without a platform configuration.

apiVIP

(Optional) The virtual IP address for Kubernetes API communication.

This setting must either be provided in the install-config.yaml file as a reserved IP from the MachineNetwork or pre-configured in the DNS so that the default name resolves correctly. Use the virtual IP address and not the FQDN when adding a value to the apiVIP configuration setting in the install-config.yaml file. The IP address must be from the primary IPv4 network when using dual stack networking. If not set, the installer uses api.<cluster_name>.<base_domain> to derive the IP address from the DNS.

disableCertificateVerification

False

redfish and redfish-virtualmedia need this parameter to manage BMC addresses. The value should be True when using a self-signed certificate for BMC addresses.

ingressVIP

(Optional) The virtual IP address for ingress traffic.

This setting must either be provided in the install-config.yaml file as a reserved IP from the MachineNetwork or pre-configured in the DNS so that the default name resolves correctly. Use the virtual IP address and not the FQDN when adding a value to the ingressVIP configuration setting in the install-config.yaml file. The IP address must be from the primary IPv4 network when using dual stack networking. If not set, the installer uses test.apps.<cluster_name>.<base_domain> to derive the IP address from the DNS.

Table 2. Optional Parameters
Parameters Default Description

provisioningDHCPRange

172.22.0.10,172.22.0.100