Snapshot failure / Web interface connection issues


Nov 29, 2019
Hi, I have recently inherited a proxmox server which unfortunately seems to be having a number of issues, and with only a basic linux knowledge I am as far unable to find the causes:

Currently snapshots are scheduled to be taken every day, but for some reason fail causing the containers to stay locked and not start up again. Only after manually unlocking and rebooting will they restart. The backups are stored in a RAID1 array which reports it has plenty of free space available. I have tried searching logs to find more information on this, but have not had any luck finding anything so far. (If anyone can confirm which log file this would be in, that would be a great help).

The web interface also appears to be having communication issues, the containers/VMs are greyed out with 'unknown' status, and when trying to view the storage in the web GUI a "communication failure (0)" error is shown. (Using SSH I can see they are actually running). I have tried restarting pvedaemon, pveproxy & pvestatd but this doesn't seem to solve the problem.

I have also noticed that in the list of proxmox packages, quite a few of them are marked as "not correctly installed". I plan on trying an update to try and fix this, but does anyone know if this could be causing any of the issues mentioned?

I can provide further screenshots/log files if they may help.

Many Thanks.

Last edited:
please try to (re-)install the packages marked as not correctly installed. In the best case running
apt install <list of packages>
should be enough. Since corosync is responsible for cluster communication, it not being installed correctly might very well be the cause of your issues. If problems persist, /var/log/syslog and journalctl -b can help to get a general idea of what's going on.


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