Proxmox Backup Server restored. Unable to restore old backups


New Member
Nov 26, 2023
Hello everyone,

I am having difficulty restoring my backups.Unfortunately, the error message isn't helping either:

recovering backed-up configuration from 'restooooooore:backup/ct/102/2023-11-26T18:49:00Z'
Formatting '/var/lib/vz/images/103/vm-103-disk-0.raw', fmt=raw size=8589934592 preallocation=off
Creating filesystem with 2097152 4k blocks and 524288 inodes
Filesystem UUID: 6fc708f7-182e-40d4-b2be-442a96f3e362
Superblock backups stored on blocks:
    32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632
restoring 'restooooooore:backup/ct/102/2023-11-26T18:49:00Z' now..
Error: error extracting archive - failed to initialize extractor
TASK ERROR: unable to restore CT 103 - command 'lxc-usernsexec -m u:0:100000:65536 -m g:0:100000:65536 -- /usr/bin/proxmox-backup-client restore '--crypt-mode=none' ct/102/2023-11-26T18:49:00Z root.pxar /var/lib/lxc/103/rootfs --allow-existing-dirs --repository root@pam@' failed: exit code 255

A few notes:
PBS is running virtually.
External USB HDD is passed through (FS ext4).
CT ran on ZFS.
Systems are up to date

It would be great if someone could provide support.
Also happy to receive help in German.
I am a complete beginner, so please be considerate i am still learning.

Best regards
Last edited:
anything visible in the PBS server side logs?
Did the securing of the PBS overlap with the securing of the containers? So does the problem occur with every backup or only specifically with this one?
I found the error myself.
I wanted to integrate my existing datastore into the PBS via the GUI.

The following error message:
TASK ERROR: unable to create chunk store 'store1' subdir "/mnt/datastore/BackupStorage/.chunks" - EEXIST: File exists

I, being foolish, thought:
Just delete the .chunks.
Datastore could be mounted without any issues. However, backups could not be restored.

I've abandoned the idea of restoring the backups

The following entry helped me:

Thanks for your quick support!!!


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