when adding nodes to a cluster, can their local-zfs storage be shared between nodes? this is the loca-zfs pool that was created during the proxmox install.
What I do is: "zfs-local" exists on all cluster members. I do replicate some VMs from one to the other nodes. When one node fails (or when I do maintenance) I can start that VM on this other node.
Replication is the key to "a poor mans shared storage" - with several drawbacks like data loss between replication intervals and usage of space on all nodes.