Installing kernel-devel package

Install kernel-devel package on Hosted Control Plane nodes.

1. To install the kernel-devel package on the worker nodes of a Hosted Control Plane cluster, create a configmap in the same namespace where the hosted cluster is created.
   In the following example, the hosted cluster is created in the bm04 namespace:

   kind: ConfigMap
   apiVersion: v1
   metadata:
     name: kernel-devel-worker-416
     namespace: bm04
   data:
     config: |
       apiVersion: machineconfiguration.openshift.io/v1
       kind: MachineConfig
       metadata:
         labels:
           machineconfiguration.openshift.io/role: worker
         name: kernel-devel-worker-416
       spec:
         config:
           ignition:
             version: 3.2.0
         extensions:
           - kernel-devel

2. After you create the configmap, update the corresponding NodePool CR of the hosted cluster in the same namespace by referencing the ConfigMap name under the config section:

   apiVersion: hypershift.openshift.io/v1beta1
   kind: NodePool
   metadata:
     name: nodepool-bm04-1
     namespace: bm04
   spec:
     arch: amd64
     clusterName: bm04
     config:
       - name: kernel-devel-worker-416
     management:
       autoRepair: false
       replace:
         rollingUpdate:
           maxSurge: 1
           maxUnavailable: 0
         strategy: RollingUpdate
       upgradeType: InPlace
     platform:
       agent:
         agentLabelSelector: {}
       type: Agent
     release:
       image: 'quay.io/openshift-release-dev/ocp-release:4.16.37-multi'
     replicas: 8

3. After you apply the changes, the nodes in the Hosted Control Plane cluster will begin rebooting.
   After all nodes are rebooted, verify that the kernel-devel package is installed on each node:

   sh-5.1# date; rpm -qa | grep kernel
   Fri Apr 25 13:07:13 UTC 2025
   kernel-modules-core-5.14.0-427.57.1.el9_4.x86_64
   kernel-core-5.14.0-427.57.1.el9_4.x86_64
   kernel-modules-5.14.0-427.57.1.el9_4.x86_64
   kernel-5.14.0-427.57.1.el9_4.x86_64
   kernel-modules-extra-5.14.0-427.57.1.el9_4.x86_64
   kernel-headers-5.14.0-427.57.1.el9_4.x86_64
   kernel-devel-5.14.0-427.57.1.el9_4.x86_64