Problems with the backup of my LXC - exit code 255


Dec 15, 2020
Dear all,

I'm really struggling with the backup of my LXC. Not sure what is the problem and how to sort it.

INFO: starting new backup job: vzdump 2000 --storage PBS --mode stop --notes-template '{{guestname}}' --node pve --remove 0
INFO: Starting Backup of VM 2000 (lxc)
INFO: Backup started at 2023-11-05 13:16:02
INFO: status = running
INFO: backup mode: stop
INFO: ionice priority: 7
INFO: CT Name: docker
INFO: including mount point rootfs ('/') in backup
INFO: excluding bind mount point mp0 ('/home/media') from backup (not a volume)
INFO: stopping virtual guest
INFO: creating Proxmox Backup Server archive 'ct/2000/2023-11-05T11:16:02Z'
INFO: run: /usr/bin/proxmox-backup-client backup --crypt-mode=none pct.conf:/mnt/vztmp/vzdumptmp32123_2000//etc/vzdump/pct.conf root.pxar:/mnt/vzsnap0 --include-dev /mnt/vzsnap0/./ --skip-lost-and-found --exclude=/tmp/?* --exclude=/var/tmp/?* --exclude=/var/run/?*.pid --backup-type ct --backup-id 2000 --backup-time 1699182962 --repository root@pam@
INFO: Starting backup: ct/2000/2023-11-05T11:16:02Z
INFO: Client name: pve
INFO: Starting backup protocol: Sun Nov  5 13:16:15 2023
INFO: Downloading previous manifest (Sun Oct 29 12:54:02 2023)
INFO: Upload config file '/mnt/vztmp/vzdumptmp32123_2000//etc/vzdump/pct.conf' to 'root@pam@' as pct.conf.blob
INFO: Upload directory '/mnt/vzsnap0' to 'root@pam@' as root.pxar.didx
INFO: catalog upload error - channel closed
INFO: Error: detected chunk with wrong digest.
INFO: restarting vm
explicitly configured lxc.apparmor.profile overrides the following settings: features:nesting
INFO: guest is online again after 35 seconds
ERROR: Backup of VM 2000 failed - command '/usr/bin/proxmox-backup-client backup '--crypt-mode=none' pct.conf:/mnt/vztmp/vzdumptmp32123_2000//etc/vzdump/pct.conf root.pxar:/mnt/vzsnap0 --include-dev /mnt/vzsnap0/./ --skip-lost-and-found '--exclude=/tmp/?*' '--exclude=/var/tmp/?*' '--exclude=/var/run/?*.pid' --backup-type ct --backup-id 2000 --backup-time 1699182962 --repository root@pam@' failed: exit code 255
INFO: Failed at 2023-11-05 13:16:37
INFO: Backup job finished with errors
TASK ERROR: job errors

After this, it brings Proxmox totally down.

Last edited:


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