Problem with LXC Backup


New Member
Dec 9, 2019
Hi Proxmox Community.

We have a problem with our LXC Backup on a single Proxmox Node.

We have configured two LXC Container, where one LXC Container alway backups fine without problem, but the second LXC Container have some issues.
Both backups to a NAS with different CIFS Shares.

Here is the log from the faulty LXC Backup:

INFO: starting new backup job: vzdump 10252 --storage <CIFS-Share> --remove 0 --mode snapshot --node <pvenode> --compress lzo
INFO: filesystem type on dumpdir is 'cifs' -using /var/tmp/vzdumptmp16995 for temporary files
INFO: Starting Backup of VM 10252 (lxc)
INFO: Backup started at 2019-12-09 11:03:11
INFO: status = running
INFO: CT Name: <container-name>
INFO: backup mode: snapshot
INFO: ionice priority: 7
INFO: create storage snapshot 'vzdump'
  Logical volume "snap_vm-10252-disk-1_vzdump" created.
INFO: creating archive '/mnt/pve/<CIFS-Share>/dump/vzdump-lxc-10252-2019_12_09-11_03_10.tar.lzo'
INFO: tar: ./var/log/btmp: Cannot open: Permission denied
INFO: tar: ./var/log/mail.err: Cannot open: Permission denied
INFO: Total bytes written: 5239808000 (4.9GiB, 16MiB/s)
INFO: tar: Exiting with failure status due to previous errors
INFO: remove vzdump snapshot
  Logical volume "snap_vm-10252-disk-1_vzdump" successfully removed
ERROR: Backup of VM 10252 failed - command 'set -o pipefail && lxc-usernsexec -m u:0:100000:65536 -m g:0:100000:65536 -- tar cpf - --totals --one-file-system -p --sparse --numeric-owner --acls --xattrs '--xattrs-include=user.*' '--xattrs-include=security.capability' '--warning=no-file-ignored' '--warning=no-xattr-write' --one-file-system '--warning=no-file-ignored' '--directory=/var/tmp/vzdumptmp16995' ./etc/vzdump/pct.conf ./etc/vzdump/pct.fw '--directory=/mnt/vzsnap0' --no-anchored '--exclude=lost+found' --anchored '--exclude=./tmp/?*' '--exclude=./var/tmp/?*' '--exclude=./var/run/?*.pid' ./ | lzop >/mnt/pve/<CIFS-Share>/dump/vzdump-lxc-10252-2019_12_09-11_03_10.tar.dat' failed: exit code 2
INFO: Failed at 2019-12-09 11:08:41
INFO: Backup job finished with errors
TASK ERROR: job errors

If you need some more infos, i will post them.

Cheers Basti

Sorry for the delayed answer. I just heard from my co-worker that this was a permission issue.
After changing the permission the backup just runs fine.

Thanks for you input.

Cheers Basti


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