How do I figure out what’s going on? It happened 2 times the last 3 days. Running kubectl describe/logs on the pods and nodes does not reveal anything.
Any help is appreciated, thanks!
Your cluster and nodes are likely being auto-upgraded If you take a look at the release notes for the ~monthly releases (for example R16), you’ll see the various auto-upgrades that take place.
You can run the gcloud container operations list command and you should see upgrade operations.
If you’d like more control over if/when your cluster control plane and/or nodes are upgrades, you can set up maintenance windows and/or maintenance exclusions.
Also, I note if you’re using a tool such as terraform and specifying the version directly. When you apply such config you’ll downgrade and GKE will upgrade you again in next cycle. So can make restarts more frequent