Troubleshoot

I have no idea, what these errors mean. $searchengine and manual pages didn't reveal anything.

That's the first one. It occurs during boot time. Might be a bug somewhere, recently introduced in Debian Sid.

kernel: [ ... ] cgroup: cgroup2: unknown option "nsdelegate"

And that's the second one. It simply occurred. No real issue with NFS though.

kernel: [ ... ] nfs: RPC call returned error 22
kernel: [ ... ] NFS: state manager: check lease failed on NFSv4 server XXX.XXX.XXX.XXX with error 5

Any explanation is appreciated.