PVE Troubleshooting

For some reason, the denizens of the Internet assume that all difficulties when using PVE stem from screwing up your cluster.  This is kind of odd when you consider that, sometimes, PVE servers run on their own...

qm commands fail hard

Example:

root@proxmox-pve:~# qm list
ipcc_send_rec[1] failed: Connection refused
ipcc_send_rec[2] failed: Connection refused
ipcc_send_rec[3] failed: Connection refused
Unable to load access control list: Connection refused

Nearly every Google hit is discussion about how to get your cluster working again...  :|

The actual problem, OTOH... Appears to be that, if your hostname doesn't match what's in /etc/hosts qm gets lost...