OKD 4.20 Release Issues

With OKD 4.20 officially released, several issues have surfaced. Below are brief descriptions of each issue and suggested workarounds. Please reach out if you come across additional issues.

2255: Upgrade to 4.20.0-okd-scos.0 - nodes fail to start due to incorrect runtime

Effects: Upgrades from 4.18 or lower to 4.20

Resolution: First, manually replace "runc" with "crun" in /etc/crio/crio.conf.d/01-ctrcfg-defaultRuntime on every node. Then, apply a container runtime override for the masters and workers.

apiVersion: machineconfiguration.openshift.io/v1
kind: ContainerRuntimeConfig
metadata:
  name: crun-master
spec:
  containerRuntimeConfig:
    defaultRuntime: crun
  machineConfigPoolSelector:
    matchLabels:
      pools.operator.machineconfiguration.openshift.io/master: ''

apiVersion: machineconfiguration.openshift.io/v1
kind: ContainerRuntimeConfig
metadata:
  name: crun-worker
spec:
  containerRuntimeConfig:
    defaultRuntime: crun
  machineConfigPoolSelector:
    matchLabels:
      pools.operator.machineconfiguration.openshift.io/worker: ''