LXC backup on NFS fails "chown operation not permitted" VMs backup without issue

linesquarecube

New Member
Jul 11, 2024
10
2
3
Germany
Hi,

after setting up my NAS again, I have an issue with backing up my LXCs to an NFS share. This setup used to work for both VMs and LXCs in the past, now only for VMs.

The NFS share is set up with write access (which works – VM backups succeed), and I’m using the all_squash option as well as fixed anonuid/anongid, since it’s a local share just for me and I wanted to keep things simple.

When I try to back up an LXC, I get an error saying that rsync cannot chown the temp files. If I let the backup process continue, I end up with a temp folder containing all the files, but they aren’t packaged into a tar archive as expected.

I’d appreciate any help or suggestions :)

Code:
INFO: starting new backup job: vzdump 112 --notes-template '{{guestname}}' --notification-mode auto --compress zstd --node pve --mode suspend --remove 0 --storage OpenMediaVault
INFO: Starting Backup of VM 112 (lxc)
INFO: Backup started at 2025-08-03 20:50:38
INFO: status = running
INFO: backup mode: suspend
INFO: ionice priority: 7
INFO: CT Name: Wireguard
INFO: including mount point rootfs ('/') in backup
INFO: temporary directory is on NFS, disabling xattr and acl support, consider configuring a local tmpdir via /etc/vzdump.conf
INFO: starting first sync /proc/2175/root/ to /mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/." failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/arch" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/ash" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/base64" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/bbconfig" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/cat" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/chattr" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/chgrp" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/chmod" failed: Operation not permitted (1)
ERROR: rsync: [generator] chown "/mnt/pve/OpenMediaVault/dump/vzdump-lxc-112-2025_08_03-20_50_38.tmp/bin/chown" failed: Operation not permitted (1)
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were you able to resolve this. I am running into a similar issue. I have two proxmox server, one is working but other gives the same operations not permitted issue
 
Unfortunately not. Are both of your servers running the same version of Proxmox, and are they using the same shares? Regarding the shares, do you have any special NFS or mount options set?
 
So I just fixed it.
My Server 1 has two drives. 256gb SSD and 1tb SSD. Proxmox is installed on 256ssd and 1tb is for my VM and containers. So these are the volumes on Server 1.
local
local-lvm
local_image (<-- this is the 1tb SSD)
So on server one, when I backup the images to my synology nas it worked. (In synology NFS is set for only the proxmox IP, with map all users to admin)

Server2 (which is my protectcli appliance for running opensense, pihole and nginx pm) <-- The one with the above issue.
This one only has 1 drive. So the volumes are. (On server 2 the base HDD type is zfs)
local
local-zfs
I was storing the VM and container to local instead of local-zfs. Local allowed the VM to be backed up but not the lxc container. Reading up some difference between the two, I realized local-zfs is the correct location. So after backing up (strange it allowed me to manually backup), I restored it to local-zfs and now my automated backups are working