ZFS: VM increase in size after Backup, proxmox going crazy.

[BelluX]

Hi,

like title i have a big problem with my setup.

Is a proxmox 6.0 upgraded to a 7.0.

I see that after i run a backup, snapshot or stop mode, my VM (Ubuntu 20.04) start to increase in size on /.






You can see / increased in size by 30GB after only 10 minutes, what is the cause? I'm 100% that is something connected to ZFS but i don't know how to look and how to fix this issue.

Anyone with a similar situation?

Let me know which log i need to look for understand this.

Thank you!

 

[hec]

The size is the same you have more free space.

 

[BelluX]

check /, is increased by 10% and still going...



now is 28% compared to the first image that was 18% of /

 

[BelluX]

UPDATE:

after a reboot of the VM seems solved but if i start a new backup the problem restart.





this is the situation of / after a reboot, what is causing this?

 

[Dunuin]

Where do you store your backups? If you didn't added another storage for backups the default place for backups is "/var/lib/vz/dump" so you are storing your backups on your root filesystem so "/" is increasing.

 

[LnxBil]

Hmm .. that is very strange and I don't think that your PVE update and the space increase in your VM are related. There is an isolation layer in between so I cannot imagine what on the PVE should have been changed to get the increase in size.

I'd suggest try to dissect the problem by trying to find out where the actual size increase is happending, e.g. by running

du -xhs * 2>/dev/null

10min appart and go then one folder down until you find the culprit. After identifing that, report back and we can inspect further.