Failed Backup

[jeffgott]

I am doing some testing with PBS and I am trying to backup one VM that fails. The VM has a CD iso image attached that resides on a Synology. If I change the CD hardware to no media, the backup works. How do I prevent this?

INFO: starting new backup job: vzdump 102 --notification-mode notification-system --all 0 --notes-template '{{guestname}}' --fleecing 0 --mode snapshot --node pve --storage PBS
INFO: Starting Backup of VM 102 (qemu)
INFO: Backup started at 2026-02-11 10:51:29
INFO: status = stopped
INFO: backup mode: stop
INFO: ionice priority: 7
INFO: VM Name: SA-9.2
INFO: include disk 'scsi0' 'local-zfs:vm-102-disk-0' 150G
INFO: creating Proxmox Backup Server archive 'vm/102/2026-02-11T15:51:29Z'
INFO: starting kvm to execute backup task
ERROR: unable to activate storage 'Synology' - directory '/mnt/pve/Synology' does not exist or is unreachable
INFO: aborting backup job
ERROR: VM 102 not running
VM 102 not running
ERROR: Backup of VM 102 failed - unable to activate storage 'Synology' - directory '/mnt/pve/Synology' does not exist or is unreachable
INFO: Failed at 2026-02-11 10:51:29
INFO: Backup job finished with errors
INFO: notified via target `mail-to-root`
TASK ERROR: job errors

 

[Chris]

Hi, seems like the storage the ISO is located on is not online/reachable. In order to backup a stopped VM, the VM will have to be started (in a frozen state), meaning however all the attached disks are expected to be present.

So either you remove the ISO (if no longer required? Is this the installation ISO?), or you must assure the storage the iso resides on is available. You might also place the ISO on a local storage if the NAS cannot be online (this limits online migration however).

 

[jeffgott]

Hi, seems like the storage the ISO is located on is not online/reachable. In order to backup a stopped VM, the VM will have to be started (in a frozen state), meaning however all the attached disks are expected to be present.

So either you remove the ISO (if no longer required? Is this the installation ISO?), or you must assure the storage the iso resides on is available. You might also place the ISO on a local storage if the NAS cannot be online (this limits online migration however).

The synology is online 24/7. Are you saying that it needs to be reachable reachable by the PBS server? Do I need to add it to the PBS server?

 

[Chris]

unable to activate storage 'Synology' - directory '/mnt/pve/Synology' does not exist or is unreachable

The PVE host seems however to not be able to reach it, according to the log output. Check the status with pvesm status, double check your storage config e.g. via cat /etc/pve/storage.cfg and have a look at the systemd journal for errors with respect to the storage.

Are you saying that it needs to be reachable reachable by the PBS server? Do I need to add it to the PBS server?

No, it must be reachable by the PVE host where the VM is located on.

 

[jeffgott]

The PVE host seems however to not be able to reach it, according to the log output. Check the status with pvesm status, double check your storage config e.g. via cat /etc/pve/storage.cfg and have a look at the systemd journal for errors with respect to the storage.


No, it must be reachable by the PVE host where the VM is located on.

I figured it out. The IP address of the PVE server was not defined in NFS permissions on the Synology.