Chapter 5. Manually installing a single-node OpenShift cluster with GitOps ZTP


You can deploy a managed single-node OpenShift cluster by using Red Hat Advanced Cluster Management (RHACM) and the assisted service.

Note

If you are creating multiple managed clusters, use the SiteConfig method described in Deploying far edge sites with ZTP.

Important

The target bare-metal host must meet the networking, firmware, and hardware requirements listed in Recommended cluster configuration for vDU application workloads.

5.1. Generating GitOps ZTP installation and configuration CRs manually

Use the generator entrypoint for the ztp-site-generate container to generate the site installation and configuration custom resource (CRs) for a cluster based on SiteConfig and PolicyGenerator CRs.

Prerequisites

  • You have installed the OpenShift CLI (oc).
  • You have logged in to the hub cluster as a user with cluster-admin privileges.

Procedure

  1. Create an output folder by running the following command:

    $ mkdir -p ./out
  2. Export the argocd directory from the ztp-site-generate container image:

    $ podman run --log-driver=none --rm registry.redhat.io/openshift4/ztp-site-generate-rhel8:v4.16 extract /home/ztp --tar | tar x -C ./out

    The ./out directory has the reference PolicyGenerator and SiteConfig CRs in the out/argocd/example/ folder.

    Example output

    out
     └── argocd
          └── example
               ├── acmpolicygenerator
               │     ├── {policy-prefix}common-ranGen.yaml
               │     ├── {policy-prefix}example-sno-site.yaml
               │     ├── {policy-prefix}group-du-sno-ranGen.yaml
               │     ├── {policy-prefix}group-du-sno-validator-ranGen.yaml
               │     ├── ...
               │     ├── kustomization.yaml
               │     └── ns.yaml
               └── siteconfig
                      ├── example-sno.yaml
                      ├── KlusterletAddonConfigOverride.yaml
                      └── kustomization.yaml

  3. Create an output folder for the site installation CRs:

    $ mkdir -p ./site-install
  4. Modify the example SiteConfig CR for the cluster type that you want to install. Copy example-sno.yaml to site-1-sno.yaml and modify the CR to match the details of the site and bare-metal host that you want to install, for example:

    # example-node1-bmh-secret & assisted-deployment-pull-secret need to be created under same namespace example-sno
    ---
    apiVersion: ran.openshift.io/v1
    kind: SiteConfig
    metadata:
      name: "example-sno"
      namespace: "example-sno"
    spec:
      baseDomain: "example.com"
      pullSecretRef:
        name: "assisted-deployment-pull-secret"
      clusterImageSetNameRef: "openshift-4.16"
      sshPublicKey: "ssh-rsa AAAA..."
      clusters:
        - clusterName: "example-sno"
          networkType: "OVNKubernetes"
          # installConfigOverrides is a generic way of passing install-config
          # parameters through the siteConfig.  The 'capabilities' field configures
          # the composable openshift feature.  In this 'capabilities' setting, we
          # remove all the optional set of components.
          # Notes:
          # - OperatorLifecycleManager is needed for 4.15 and later
          # - NodeTuning is needed for 4.13 and later, not for 4.12 and earlier
          # - Ingress is needed for 4.16 and later
          installConfigOverrides: |
            {
              "capabilities": {
                "baselineCapabilitySet": "None",
                "additionalEnabledCapabilities": [
                  "NodeTuning",
                  "OperatorLifecycleManager",
                  "Ingress"
                ]
              }
            }
          # It is strongly recommended to include crun manifests as part of the additional install-time manifests for 4.13+.
          # The crun manifests can be obtained from source-crs/optional-extra-manifest/ and added to the git repo ie.sno-extra-manifest.
          # extraManifestPath: sno-extra-manifest
          clusterLabels:
            # These example cluster labels correspond to the bindingRules in the PolicyGenTemplate examples
            du-profile: "latest"
            # These example cluster labels correspond to the bindingRules in the PolicyGenTemplate examples in ../policygentemplates:
            # ../policygentemplates/common-ranGen.yaml will apply to all clusters with 'common: true'
            common: true
            # ../policygentemplates/group-du-sno-ranGen.yaml will apply to all clusters with 'group-du-sno: ""'
            group-du-sno: ""
            # ../policygentemplates/example-sno-site.yaml will apply to all clusters with 'sites: "example-sno"'
            # Normally this should match or contain the cluster name so it only applies to a single cluster
            sites: "example-sno"
          clusterNetwork:
            - cidr: 1001:1::/48
              hostPrefix: 64
          machineNetwork:
            - cidr: 1111:2222:3333:4444::/64
          serviceNetwork:
            - 1001:2::/112
          additionalNTPSources:
            - 1111:2222:3333:4444::2
          # Initiates the cluster for workload partitioning. Setting specific reserved/isolated CPUSets is done via PolicyTemplate
          # please see Workload Partitioning Feature for a complete guide.
          cpuPartitioningMode: AllNodes
          # Optionally; This can be used to override the KlusterletAddonConfig that is created for this cluster:
          #crTemplates:
          #  KlusterletAddonConfig: "KlusterletAddonConfigOverride.yaml"
          nodes:
            - hostName: "example-node1.example.com"
              role: "master"
              # Optionally; This can be used to configure desired BIOS setting on a host:
              #biosConfigRef:
              #  filePath: "example-hw.profile"
              bmcAddress: "idrac-virtualmedia+https://[1111:2222:3333:4444::bbbb:1]/redfish/v1/Systems/System.Embedded.1"
              bmcCredentialsName:
                name: "example-node1-bmh-secret"
              bootMACAddress: "AA:BB:CC:DD:EE:11"
              # Use UEFISecureBoot to enable secure boot
              bootMode: "UEFI"
              rootDeviceHints:
                deviceName: "/dev/disk/by-path/pci-0000:01:00.0-scsi-0:2:0:0"
              # disk partition at `/var/lib/containers` with ignitionConfigOverride. Some values must be updated. See DiskPartitionContainer.md for more details
              ignitionConfigOverride: |
                {
                  "ignition": {
                    "version": "3.2.0"
                  },
                  "storage": {
                    "disks": [
                      {
                        "device": "/dev/disk/by-id/wwn-0x6b07b250ebb9d0002a33509f24af1f62",
                        "partitions": [
                          {
                            "label": "var-lib-containers",
                            "sizeMiB": 0,
                            "startMiB": 250000
                          }
                        ],
                        "wipeTable": false
                      }
                    ],
                    "filesystems": [
                      {
                        "device": "/dev/disk/by-partlabel/var-lib-containers",
                        "format": "xfs",
                        "mountOptions": [
                          "defaults",
                          "prjquota"
                        ],
                        "path": "/var/lib/containers",
                        "wipeFilesystem": true
                      }
                    ]
                  },
                  "systemd": {
                    "units": [
                      {
                        "contents": "# Generated by Butane\n[Unit]\nRequires=systemd-fsck@dev-disk-by\\x2dpartlabel-var\\x2dlib\\x2dcontainers.service\nAfter=systemd-fsck@dev-disk-by\\x2dpartlabel-var\\x2dlib\\x2dcontainers.service\n\n[Mount]\nWhere=/var/lib/containers\nWhat=/dev/disk/by-partlabel/var-lib-containers\nType=xfs\nOptions=defaults,prjquota\n\n[Install]\nRequiredBy=local-fs.target",
                        "enabled": true,
                        "name": "var-lib-containers.mount"
                      }
                    ]
                  }
                }
              nodeNetwork:
                interfaces:
                  - name: eno1
                    macAddress: "AA:BB:CC:DD:EE:11"
                config:
                  interfaces:
                    - name: eno1
                      type: ethernet
                      state: up
                      ipv4:
                        enabled: false
                      ipv6:
                        enabled: true
                        address:
                          # For SNO sites with static IP addresses, the node-specific,
                          # API and Ingress IPs should all be the same and configured on
                          # the interface
                          - ip: 1111:2222:3333:4444::aaaa:1
                            prefix-length: 64
                  dns-resolver:
                    config:
                      search:
                        - example.com
                      server:
                        - 1111:2222:3333:4444::2
                  routes:
                    config:
                      - destination: ::/0
                        next-hop-interface: eno1
                        next-hop-address: 1111:2222:3333:4444::1
                        table-id: 254
    Note

    Once you have extracted reference CR configuration files from the out/extra-manifest directory of the ztp-site-generate container, you can use extraManifests.searchPaths to include the path to the git directory containing those files. This allows the GitOps ZTP pipeline to apply those CR files during cluster installation. If you configure a searchPaths directory, the GitOps ZTP pipeline does not fetch manifests from the ztp-site-generate container during site installation.

  5. Generate the Day 0 installation CRs by processing the modified SiteConfig CR site-1-sno.yaml by running the following command:

    $ podman run -it --rm -v `pwd`/out/argocd/example/siteconfig:/resources:Z -v `pwd`/site-install:/output:Z,U registry.redhat.io/openshift4/ztp-site-generate-rhel8:v4.16 generator install site-1-sno.yaml /output

    Example output

    site-install
    └── site-1-sno
        ├── site-1_agentclusterinstall_example-sno.yaml
        ├── site-1-sno_baremetalhost_example-node1.example.com.yaml
        ├── site-1-sno_clusterdeployment_example-sno.yaml
        ├── site-1-sno_configmap_example-sno.yaml
        ├── site-1-sno_infraenv_example-sno.yaml
        ├── site-1-sno_klusterletaddonconfig_example-sno.yaml
        ├── site-1-sno_machineconfig_02-master-workload-partitioning.yaml
        ├── site-1-sno_machineconfig_predefined-extra-manifests-master.yaml
        ├── site-1-sno_machineconfig_predefined-extra-manifests-worker.yaml
        ├── site-1-sno_managedcluster_example-sno.yaml
        ├── site-1-sno_namespace_example-sno.yaml
        └── site-1-sno_nmstateconfig_example-node1.example.com.yaml

  6. Optional: Generate just the Day 0 MachineConfig installation CRs for a particular cluster type by processing the reference SiteConfig CR with the -E option. For example, run the following commands:

    1. Create an output folder for the MachineConfig CRs:

      $ mkdir -p ./site-machineconfig
    2. Generate the MachineConfig installation CRs:

      $ podman run -it --rm -v `pwd`/out/argocd/example/siteconfig:/resources:Z -v `pwd`/site-machineconfig:/output:Z,U registry.redhat.io/openshift4/ztp-site-generate-rhel8:v4.16 generator install -E site-1-sno.yaml /output

      Example output

      site-machineconfig
      └── site-1-sno
          ├── site-1-sno_machineconfig_02-master-workload-partitioning.yaml
          ├── site-1-sno_machineconfig_predefined-extra-manifests-master.yaml
          └── site-1-sno_machineconfig_predefined-extra-manifests-worker.yaml

  7. Generate and export the Day 2 configuration CRs using the reference PolicyGenerator CRs from the previous step. Run the following commands:

    1. Create an output folder for the Day 2 CRs:

      $ mkdir -p ./ref
    2. Generate and export the Day 2 configuration CRs:

      $ podman run -it --rm -v `pwd`/out/argocd/example/acmpolicygenerator:/resources:Z -v `pwd`/ref:/output:Z,U registry.redhat.io/openshift4/ztp-site-generate-rhel8:v4.16 generator config -N . /output

      The command generates example group and site-specific PolicyGenerator CRs for single-node OpenShift, three-node clusters, and standard clusters in the ./ref folder.

      Example output

      ref
       └── customResource
            ├── common
            ├── example-multinode-site
            ├── example-sno
            ├── group-du-3node
            ├── group-du-3node-validator
            │    └── Multiple-validatorCRs
            ├── group-du-sno
            ├── group-du-sno-validator
            ├── group-du-standard
            └── group-du-standard-validator
                 └── Multiple-validatorCRs

  8. Use the generated CRs as the basis for the CRs that you use to install the cluster. You apply the installation CRs to the hub cluster as described in "Installing a single managed cluster". The configuration CRs can be applied to the cluster after cluster installation is complete.

Verification

  • Verify that the custom roles and labels are applied after the node is deployed:

    $ oc describe node example-node.example.com

Example output

Name:   example-node.example.com
Roles:  control-plane,example-label,master,worker
Labels: beta.kubernetes.io/arch=amd64
        beta.kubernetes.io/os=linux
        custom-label/parameter1=true
        kubernetes.io/arch=amd64
        kubernetes.io/hostname=cnfdf03.telco5gran.eng.rdu2.redhat.com
        kubernetes.io/os=linux
        node-role.kubernetes.io/control-plane=
        node-role.kubernetes.io/example-label= 1
        node-role.kubernetes.io/master=
        node-role.kubernetes.io/worker=
        node.openshift.io/os_id=rhcos

1
The custom label is applied to the node.

5.2. Creating the managed bare-metal host secrets

Add the required Secret custom resources (CRs) for the managed bare-metal host to the hub cluster. You need a secret for the GitOps Zero Touch Provisioning (ZTP) pipeline to access the Baseboard Management Controller (BMC) and a secret for the assisted installer service to pull cluster installation images from the registry.

Note

The secrets are referenced from the SiteConfig CR by name. The namespace must match the SiteConfig namespace.

Procedure

  1. Create a YAML secret file containing credentials for the host Baseboard Management Controller (BMC) and a pull secret required for installing OpenShift and all add-on cluster Operators:

    1. Save the following YAML as the file example-sno-secret.yaml:

      apiVersion: v1
      kind: Secret
      metadata:
        name: example-sno-bmc-secret
        namespace: example-sno 1
      data: 2
        password: <base64_password>
        username: <base64_username>
      type: Opaque
      ---
      apiVersion: v1
      kind: Secret
      metadata:
        name: pull-secret
        namespace: example-sno  3
      data:
        .dockerconfigjson: <pull_secret> 4
      type: kubernetes.io/dockerconfigjson
      1
      Must match the namespace configured in the related SiteConfig CR
      2
      Base64-encoded values for password and username
      3
      Must match the namespace configured in the related SiteConfig CR
      4
      Base64-encoded pull secret
  2. Add the relative path to example-sno-secret.yaml to the kustomization.yaml file that you use to install the cluster.

5.3. Configuring Discovery ISO kernel arguments for manual installations using GitOps ZTP

The GitOps Zero Touch Provisioning (ZTP) workflow uses the Discovery ISO as part of the OpenShift Container Platform installation process on managed bare-metal hosts. You can edit the InfraEnv resource to specify kernel arguments for the Discovery ISO. This is useful for cluster installations with specific environmental requirements. For example, configure the rd.net.timeout.carrier kernel argument for the Discovery ISO to facilitate static networking for the cluster or to receive a DHCP address before downloading the root file system during installation.

Note

In OpenShift Container Platform 4.16, you can only add kernel arguments. You can not replace or delete kernel arguments.

Prerequisites

  • You have installed the OpenShift CLI (oc).
  • You have logged in to the hub cluster as a user with cluster-admin privileges.
  • You have manually generated the installation and configuration custom resources (CRs).

Procedure

  1. Edit the spec.kernelArguments specification in the InfraEnv CR to configure kernel arguments:
apiVersion: agent-install.openshift.io/v1beta1
kind: InfraEnv
metadata:
  name: <cluster_name>
  namespace: <cluster_name>
spec:
  kernelArguments:
    - operation: append 1
      value: audit=0 2
    - operation: append
      value: trace=1
  clusterRef:
    name: <cluster_name>
    namespace: <cluster_name>
  pullSecretRef:
    name: pull-secret
1
Specify the append operation to add a kernel argument.
2
Specify the kernel argument you want to configure. This example configures the audit kernel argument and the trace kernel argument.
Note

The SiteConfig CR generates the InfraEnv resource as part of the day-0 installation CRs.

Verification

To verify that the kernel arguments are applied, after the Discovery image verifies that OpenShift Container Platform is ready for installation, you can SSH to the target host before the installation process begins. At that point, you can view the kernel arguments for the Discovery ISO in the /proc/cmdline file.

  1. Begin an SSH session with the target host:

    $ ssh -i /path/to/privatekey core@<host_name>
  2. View the system’s kernel arguments by using the following command:

    $ cat /proc/cmdline

5.4. Installing a single managed cluster

You can manually deploy a single managed cluster using the assisted service and Red Hat Advanced Cluster Management (RHACM).

Prerequisites

  • You have installed the OpenShift CLI (oc).
  • You have logged in to the hub cluster as a user with cluster-admin privileges.
  • You have created the baseboard management controller (BMC) Secret and the image pull-secret Secret custom resources (CRs). See "Creating the managed bare-metal host secrets" for details.
  • Your target bare-metal host meets the networking and hardware requirements for managed clusters.

Procedure

  1. Create a ClusterImageSet for each specific cluster version to be deployed, for example clusterImageSet-4.16.yaml. A ClusterImageSet has the following format:

    apiVersion: hive.openshift.io/v1
    kind: ClusterImageSet
    metadata:
      name: openshift-4.16.0 1
    spec:
       releaseImage: quay.io/openshift-release-dev/ocp-release:4.16.0-x86_64 2
    1
    The descriptive version that you want to deploy.
    2
    Specifies the releaseImage to deploy and determines the operating system image version. The discovery ISO is based on the image version as set by releaseImage, or the latest version if the exact version is unavailable.
  2. Apply the clusterImageSet CR:

    $ oc apply -f clusterImageSet-4.16.yaml
  3. Create the Namespace CR in the cluster-namespace.yaml file:

    apiVersion: v1
    kind: Namespace
    metadata:
         name: <cluster_name> 1
         labels:
            name: <cluster_name> 2
    1 2
    The name of the managed cluster to provision.
  4. Apply the Namespace CR by running the following command:

    $ oc apply -f cluster-namespace.yaml
  5. Apply the generated day-0 CRs that you extracted from the ztp-site-generate container and customized to meet your requirements:

    $ oc apply -R ./site-install/site-sno-1

5.5. Monitoring the managed cluster installation status

Ensure that cluster provisioning was successful by checking the cluster status.

Prerequisites

  • All of the custom resources have been configured and provisioned, and the Agent custom resource is created on the hub for the managed cluster.

Procedure

  1. Check the status of the managed cluster:

    $ oc get managedcluster

    True indicates the managed cluster is ready.

  2. Check the agent status:

    $ oc get agent -n <cluster_name>
  3. Use the describe command to provide an in-depth description of the agent’s condition. Statuses to be aware of include BackendError, InputError, ValidationsFailing, InstallationFailed, and AgentIsConnected. These statuses are relevant to the Agent and AgentClusterInstall custom resources.

    $ oc describe agent -n <cluster_name>
  4. Check the cluster provisioning status:

    $ oc get agentclusterinstall -n <cluster_name>
  5. Use the describe command to provide an in-depth description of the cluster provisioning status:

    $ oc describe agentclusterinstall -n <cluster_name>
  6. Check the status of the managed cluster’s add-on services:

    $ oc get managedclusteraddon -n <cluster_name>
  7. Retrieve the authentication information of the kubeconfig file for the managed cluster:

    $ oc get secret -n <cluster_name> <cluster_name>-admin-kubeconfig -o jsonpath={.data.kubeconfig} | base64 -d > <directory>/<cluster_name>-kubeconfig

5.6. Troubleshooting the managed cluster

Use this procedure to diagnose any installation issues that might occur with the managed cluster.

Procedure

  1. Check the status of the managed cluster:

    $ oc get managedcluster

    Example output

    NAME            HUB ACCEPTED   MANAGED CLUSTER URLS   JOINED   AVAILABLE   AGE
    SNO-cluster     true                                   True     True      2d19h

    If the status in the AVAILABLE column is True, the managed cluster is being managed by the hub.

    If the status in the AVAILABLE column is Unknown, the managed cluster is not being managed by the hub. Use the following steps to continue checking to get more information.

  2. Check the AgentClusterInstall install status:

    $ oc get clusterdeployment -n <cluster_name>

    Example output

    NAME        PLATFORM            REGION   CLUSTERTYPE   INSTALLED    INFRAID    VERSION  POWERSTATE AGE
    Sno0026    agent-baremetal                               false                          Initialized
    2d14h

    If the status in the INSTALLED column is false, the installation was unsuccessful.

  3. If the installation failed, enter the following command to review the status of the AgentClusterInstall resource:

    $ oc describe agentclusterinstall -n <cluster_name> <cluster_name>
  4. Resolve the errors and reset the cluster:

    1. Remove the cluster’s managed cluster resource:

      $ oc delete managedcluster <cluster_name>
    2. Remove the cluster’s namespace:

      $ oc delete namespace <cluster_name>

      This deletes all of the namespace-scoped custom resources created for this cluster. You must wait for the ManagedCluster CR deletion to complete before proceeding.

    3. Recreate the custom resources for the managed cluster.

5.7. RHACM generated cluster installation CRs reference

Red Hat Advanced Cluster Management (RHACM) supports deploying OpenShift Container Platform on single-node clusters, three-node clusters, and standard clusters with a specific set of installation custom resources (CRs) that you generate using SiteConfig CRs for each site.

Note

Every managed cluster has its own namespace, and all of the installation CRs except for ManagedCluster and ClusterImageSet are under that namespace. ManagedCluster and ClusterImageSet are cluster-scoped, not namespace-scoped. The namespace and the CR names match the cluster name.

The following table lists the installation CRs that are automatically applied by the RHACM assisted service when it installs clusters using the SiteConfig CRs that you configure.

Table 5.1. Cluster installation CRs generated by RHACM
CRDescriptionUsage

BareMetalHost

Contains the connection information for the Baseboard Management Controller (BMC) of the target bare-metal host.

Provides access to the BMC to load and start the discovery image on the target server by using the Redfish protocol.

InfraEnv

Contains information for installing OpenShift Container Platform on the target bare-metal host.

Used with ClusterDeployment to generate the discovery ISO for the managed cluster.

AgentClusterInstall

Specifies details of the managed cluster configuration such as networking and the number of control plane nodes. Displays the cluster kubeconfig and credentials when the installation is complete.

Specifies the managed cluster configuration information and provides status during the installation of the cluster.

ClusterDeployment

References the AgentClusterInstall CR to use.

Used with InfraEnv to generate the discovery ISO for the managed cluster.

NMStateConfig

Provides network configuration information such as MAC address to IP mapping, DNS server, default route, and other network settings.

Sets up a static IP address for the managed cluster’s Kube API server.

Agent

Contains hardware information about the target bare-metal host.

Created automatically on the hub when the target machine’s discovery image boots.

ManagedCluster

When a cluster is managed by the hub, it must be imported and known. This Kubernetes object provides that interface.

The hub uses this resource to manage and show the status of managed clusters.

KlusterletAddonConfig

Contains the list of services provided by the hub to be deployed to the ManagedCluster resource.

Tells the hub which addon services to deploy to the ManagedCluster resource.

Namespace

Logical space for ManagedCluster resources existing on the hub. Unique per site.

Propagates resources to the ManagedCluster.

Secret

Two CRs are created: BMC Secret and Image Pull Secret.

  • BMC Secret authenticates into the target bare-metal host using its username and password.
  • Image Pull Secret contains authentication information for the OpenShift Container Platform image installed on the target bare-metal host.

ClusterImageSet

Contains OpenShift Container Platform image information such as the repository and image name.

Passed into resources to provide OpenShift Container Platform images.

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