1. Reflect on Recent Actions: Consider any recent changes you might have made, such as mounting storage or shutting down VMs.

2. Check pvestatd Service: The pvestatd service is responsible for the node status in PVE. Try restarting this service.

Check Service Status:

systemctl status pvestatd

Restart Service:

systemctl restart pvestatd

3. Troubleshoot Storage Issues: If the storage remains inaccessible and shows a “communication failure,” it is likely a process hang.

Test with df Command:

df -h

If this command hangs, use:

strace df -h

The last item got stuck, and I realized instantly that this was a remote ISO library mounted on the virtual machine. I had shut down the virtual machine before the problem occurred. I restarted the virtual machine and restarted the pvestatd service, and everything was normal.

I shut down the ISO library virtual machine again, and the same problem occurred again.

If you cannot boot or remount, uninstall it with umount -l, and remove the repository in the shell.

pvesm remove iso  

The system should now function properly.

Important Reminder: If VMs are running normally but there are GUI issues, consider issues with Proxmox VE services first. Then address specific problems (e.g., storage issues) without blindly restarting the server. In a cluster environment, if a server restart is necessary, prioritize using command-line migration to avoid disrupting critical services.