Cannot upgrade from 4.9 to 4.10 due to kibe-apiserver InvalidCertsUpgradeable: Server certificates without SAN detected: {type="aggregation"}.

[Serbinmatosh]

Upgraded up to version 4.9-2-12 and Cluster operator error popped up blocking the further upgrade to 4.10.

it states that kube-apiserver should not be upgraded between minor versions: InvalidCertsUpgradeable: Server certificates without SAN detected: {type="aggregation"}. These have to be replaced to include the respective hosts in their SAN extension and not rely on the Subject's CN for the purpose of hostname verification.

Not really sure how to fix this issue, is there a documented solution for this scenario?

[JaimeMagiera]

These versions of OKD are (far) beyond those actively being worked on by the OKD Working Group. We limit active work to N and N-1. I'll convert this to a Discussion and perhaps the community can chime in.

[Serbinmatosh]

@vrutkovs is there any chance that you have come across this issue in the past, or maybe know how to resolve it ? Thanks in advance!

[Serbinmatosh]

The solution to this is that the message is a bug. A restart of the kube-apiserver-operator pod completely removed the issue.