Permission denied on LXE containers but not on VM's

Feb 24, 2016
Monterrey, Mexico
Hi, I did a v8 a fresh and new install and restored 4 vms and created brand new CT over ubuntu templates. Did a back up ALL machines but CT give this errors. Only one NFS storage is configure with proven full access.. all vms get backedup but not LXE machines. any idea?


INFO: starting new backup job: vzdump 106 --compress zstd --notes-template '{{guestname}}' --storage SYNOLOGY --node proxmox-kb1 --mode snapshot --remove 0
INFO: Starting Backup of VM 106 (lxc)
INFO: Backup started at 2023-07-06 09:18:29
INFO: status = running
INFO: CT Name: NextCloud
INFO: including mount point rootfs ('/') in backup
INFO: backup mode: snapshot
INFO: ionice priority: 7
INFO: create storage snapshot 'vzdump'
INFO: creating vzdump archive '/mnt/pve/SYNOLOGY/dump/vzdump-lxc-106-2023_07_06-09_18_29.tar.zst'
INFO: tar: /mnt/pve/SYNOLOGY/dump/vzdump-lxc-106-2023_07_06-09_18_29.tmp: Cannot open: Permission denied
INFO: tar: Error is not recoverable: exiting now
INFO: cleanup temporary 'vzdump' snapshot
ERROR: Backup of VM 106 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/SYNOLOGY/dump/vzdump-lxc-106-2023_07_06-09_18_29.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/SYNOLOGY/dump/vzdump-lxc-106-2023_07_06-09_18_29.tar.dat' failed: exit code 2
INFO: Failed at 2023-07-06 09:18:29
INFO: Backup job finished with errors
TASK ERROR: job errors
just to enlight the thread solution was to set the NFS to

Squash -> Map all users to admin on the NFS side (in my case a synology NAS)

Squash -> Map all users to admin
This indeed was the solution for me as well - exact same problem. PVE backup job with VM's and LXC's with only LXC's failing. vzdump folder is a NFS share exported from Synology NAS.


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