[SOLVED] Backup fails

[Skipping1895]

All my CM/CT backups fails with the same reason.
What is the cause of this, and what to do?

I am trying to backup to my NAS.
The NAS is connected through NFS and works fine with everything else than backups.

()
INFO: starting new backup job: vzdump 111 --compress zstd --mode snapshot --notification-mode auto --node pve --remove 0 --storage NAS --notes-template '{{guestname}}'
INFO: Starting Backup of VM 111 (lxc)
INFO: Backup started at 2024-07-14 00:30:17
INFO: status = running
INFO: CT Name: wastebin
INFO: including mount point rootfs ('/') in backup
INFO: backup mode: snapshot
INFO: ionice priority: 7
INFO: create storage snapshot 'vzdump'
  Logical volume "snap_vm-111-disk-0_vzdump" created.
INFO: creating vzdump archive '/mnt/pve/NAS/dump/vzdump-lxc-111-2024_07_14-00_30_17.tar.zst'
INFO: tar: /mnt/pve/NAS/dump/vzdump-lxc-111-2024_07_14-00_30_17.tmp: Cannot open: Permission denied
INFO: tar: Error is not recoverable: exiting now
INFO: cleanup temporary 'vzdump' snapshot
  Logical volume "snap_vm-111-disk-0_vzdump" successfully removed.
ERROR: Backup of VM 111 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/NAS/dump/vzdump-lxc-111-2024_07_14-00_30_17.tmp' ./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' ./ | zstd '--threads=1' >/mnt/pve/NAS/dump/vzdump-lxc-111-2024_07_14-00_30_17.tar.dat' failed: exit code 2
INFO: Failed at 2024-07-14 00:30:17
INFO: Backup job finished with errors
INFO: notified via target `mail-to-root`
TASK ERROR: job errors

 

[dietmar]

It is a permission problem on the NAS. I guess user "root" is not allowed to create files there.

> INFO: tar: /mnt/pve/NAS/dump/vzdump-lxc-111-2024_07_14-00_30_17.tmp: Cannot open: Permission denied

 

[fiona]

Please note that it's the unprivileged container's root user, i.e. 100000 from the host's perspective, that needs the permission.

 

[Skipping1895]

Thank you @dietmar and @fiona for your replies. Very appreciated!
I am still not sure what to do to fix it.

It should have permission to create files. I can have ISO's, VM/CT's etc. to be created/saved on there.
So I am a bit confused what permission needed or set, or where to grant this permission.
It's a Sonology NAS if that makes any useful information.

 

[fiona]

You need to configure your NAS so that the user with ID 100000 has the necessary permissions: https://forum.proxmox.com/threads/backup-of-some-lxcs-failing-permission-denied.56612/#post-579476
This is the option that worked for others:
https://forum.proxmox.com/threads/p...-containers-but-not-on-vms.130224/post-571205

 

[Skipping1895]

You need to configure your NAS so that the user with ID 100000 has the necessary permissions: https://forum.proxmox.com/threads/backup-of-some-lxcs-failing-permission-denied.56612/#post-579476
This is the option that worked for others:
https://forum.proxmox.com/threads/p...-containers-but-not-on-vms.130224/post-571205

Thank you so much!
The "Squash -> Map all users to admin on the NFS side (in my case a synology NAS)" worked for me as well.
Topic can be closed as resolved.

 

[fiona]

You can do that by using the Edit thread button at the top and selecting the [SOLVED] prefix.