I run a 3-node PVE with CEPH.
I migrated all VMs away from node 3, upgraded to the latest CEPH (Quincy) and then started the PVE 7 to 8 upgrade on node 3.
After rebooting node 3 (now PVE 8), everything seemed to work well. So I migrated two VMs, one each from node 1 (still on PVE 7) and node 2...