Backup permission denied - LXC unprivileged

tony blue

Well-Known Member
Dec 26, 2017

ich habe für Backups ein NFS Share in Proxmox angelegt. Darauf kann ich problemlos Backups von VMs oder auch von LXC privileged Containern erstellen. Wenn ich jedoch das Backup für einen unprivileged LXC Container starte bricht der Vorgang mit dieser Fehlermeldung ab:

INFO: starting new backup job: vzdump 112 --storage backupserver_virtualhost_nfs --node virtualhost --mode stop --remove 0 --compress lzo
INFO: Starting Backup of VM 112 (lxc)
INFO: Backup started at 2019-07-20 16:11:36
INFO: status = stopped
INFO: backup mode: stop
INFO: ionice priority: 7
INFO: CT Name: ubuntu-18.04-lts-plain-wan-unprivileged
INFO: creating archive '/mnt/pve/backupserver_virtualhost_nfs/dump/vzdump-lxc-112-2019_07_20-16_11_36.tar.lzo'
INFO: tar: /mnt/pve/backupserver_virtualhost_nfs/dump/vzdump-lxc-112-2019_07_20-16_11_36.tmp: Cannot open: Permission denied
INFO: tar: Error is not recoverable: exiting now
ERROR: Backup of VM 112 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=/mnt/pve/backupserver_virtualhost_nfs/dump/vzdump-lxc-112-2019_07_20-16_11_36.tmp' ./etc/vzdump/pct.conf '--directory=/mnt/vzsnap0' --no-anchored '--exclude=lost+found' --anchored '--exclude=./tmp/?*' '--exclude=./var/tmp/?*' '--exclude=./var/run/?*.pid' ./ | lzop >/mnt/pve/backupserver_virtualhost_nfs/dump/vzdump-lxc-112-2019_07_20-16_11_36.tar.dat' failed: exit code 2
INFO: Failed at 2019-07-20 16:11:36
INFO: Backup job finished with errors
TASK ERROR: job errors​

Woran könnte das liegen?

Vielen Dank!

wie ist denn mnt/pve/backupserver_virtualhost_nfs/ gemounted?
(das backup wird als user root ausgefuehrt, kann sein, dass der nfs-share nicht zulaesst, dass root files anlegt (siehe

Kannst du als root ein file auf '/mnt/pve/backupserver_virtualhost_nfs' touchen?
`touch /mnt/pve/backupserver_virtualhost_nfs/test' ?

Ich hoffe das hilft!


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