MOSK clusters update fails with stuck kubelet

Managed clusters running MOSK may fail to update to the latest Cluster release with kubelet being stuck and reporting authorization errors.

The cluster is affected by the issue if you see the Failed to make webhook authorizer request: context canceled error in the kubelet logs:

docker logs ucp-kubelet --since 5m 2>&1 | grep 'Failed to make webhook authorizer request: context canceled'

To apply the issue resolution, restart the ucp-kubelet container on the affected node(s):

ctr -n com.docker.ucp snapshot rm ucp-kubelet
docker rm -f ucp-kubelet

Note

Ignore failures in the output of the first command, if any.