Backup error - zfs error: cannot create snapshot dataset already exists

[Hugo Matos]

Hi,

Does anyone have this error?

INFO: starting new backup job: vzdump 130 --compress lzo --node local02 --storage local --mode snapshot --remove 0
INFO: filesystem type on dumpdir is 'zfs' -using /var/tmp/vzdumptmp28291 for temporary files
INFO: Starting Backup of VM 130 (lxc)
INFO: status = running
INFO: CT Name:
INFO: backup mode: snapshot
INFO: ionice priority: 7
INFO: create storage snapshot 'vzdump'
snapshot create failed: starting cleanup
no lock found trying to remove 'backup' lock
ERROR: Backup of VM 130 failed - zfs error: cannot create snapshot 'rpool/data/subvol-130-disk-2@vzdump': dataset already exists
INFO: Backup job finished with errors
TASK ERROR: job errors

I have no backup in the Backup tab but I have a vzdump in rpool/data

root@local02:~# zfs list -t snapshot
NAME USED AVAIL REFER MOUNTPOINT
rpool/data/subvol-130-disk-2@vzdump 137G - 246G -


Does anyone know how to solve this?

Thanks

 

[oguz]

You probably have an incomplete backup (something happened or you did something during a previous backup).

Just remove it with

zfs destroy rpool/data/subvol-130-disk-2@vzdump

and then try to backup again.

 

[Hugo Matos]

Thanks Oguz, it solves the problem.

 

[Gilles]

Hi,
I had the same problem on PBS and I simply solved by destroying the incomplete backup.

But the real problem is that BPS did not say anything about this problem in the log neither in report mails : I just discovered it by hand checking the PBS backup list. Is there a way to have an alert when something equivalent happened ?

Thank PROXMOX you for PBS which is a very nice piece of software and will certainly replace some of my backup scripts

 

[Curt Hall]

the above does not fix it for me:

root@proxmox4:~# zfs list -t snapshot
NAME USED AVAIL REFER MOUNTPOINT
RAIDZ/vm-200-disk-0@__migration__ 21.5G - 80.8G -

root@proxmox4:~# zfs destroy rpool/data/RAIDZ/vm-200-disk-0@__migration__
cannot open 'rpool/data/RAIDZ/vm-200-disk-0': dataset does not exist
root@proxmox4:~#

What did I do wrong?

 

[oguz]

the above does not fix it for me:

root@proxmox4:~# zfs list -t snapshot
NAME USED AVAIL REFER MOUNTPOINT
RAIDZ/vm-200-disk-0@__migration__ 21.5G - 80.8G -

root@proxmox4:~# zfs destroy rpool/data/RAIDZ/vm-200-disk-0@__migration__
cannot open 'rpool/data/RAIDZ/vm-200-disk-0': dataset does not exist
root@proxmox4:~#

What did I do wrong?

you need to do zfs destroy RAIDZ/vm-200-disk-0@__migration__ since the name of the pool is different

 

[Elliott Partridge]

I ran into this issue on a backup with multiple disks, which each had the @vzdump snapshot. I was able to delete all of them using:

zfs destroy -r tank@vzdump

Maybe there could be an option to automatically destroy any existing @vzdump snapshot prior to backup. I've had this happen several times.