What is the connectivity protocol between storage and Proxmox?
What sharing strategy did you choose? (LVM, Cluster Filesystem, Direct Lun, etc) ?
What is your configuration settings (cat /etc/pve/storage.cfg)?
What is the status of the storage from each node? (pvesm status)
What do the logs show on each node? "journalctl -n 500" "journalctl -f" etc
@rozli In the image you have provided (after error) not only the VM's & Storage, you're node (and all other nodes) looks inaccessible. Where is this node located?
Something else that appears - in the first image (working) there is no name after the "Datacenter", but in the next image (error) you have the word "prodclus01". Are we looking at the same thing? Have you made other changes - except for expanding the space?