Backups with qcow2 enabled

[florent]

@acebmxer you need to enable NBD on the backup to ensure ti works with qcow2

we 'll check for the progress bar

[acebmxer]

@florent

was already enabled. Just not Purge snapshot data when using CBT.

[florent]

@acebmxer did you enabled NBD on the network ( in the pool view ? ) is it a network accessible by the xo ?

[acebmxer]

@florent
Yes...

Think i have solved it / fixed it... I ran the errors though AI and it suggested running a full backup to reset the chain. Full backup was successfull with out issues. Running delta backup now as we speak but looks good so far.

One mistake i made is enabled the purge snapshot with CBT and now vms now failling to full backups.

[Pilow]

@acebmxer I have a new case of managing to force the fell back to full error...
i'll create a new topic for this

in the time being, if you can, do a toolstack restart on your pool when no tasks is ongoing
your backups with NBD could be better (spoiler alert : iptables rules... )

[acebmxer]

@florent

Both full and delta passed...

Full - 2026-04-17T11_32_42.906Z - backup NG.txt
Delta - 2026-04-17T13_26_54.973Z - backup NG.txt

@pilow

I just restarted tool stack on both pool master and second host. Re-edit backup job to remove the purge snapshot with cbt and re-ran a delta backup. Which still fell back to full backup.

[Pilow]

@acebmxer bottom of POOL advanced tab, is BACKUP NETWORK selected on the NBD enabled network accessible by both hosts and XOA ?

[acebmxer]

@Pilow

Was already configured...

Think this is the issue....
Network tab under pool.

Will run another delta once the current one finishes.

Edit - update

Can a warning be made if NBD is not enabled at the pool level? or make the error more clear?

I enabled the nbd at the pool level and ran another delta - 2026-04-17T14_40_39.535Z - backup NG.txt

I Then re-enable the purge snapshot in back up job and ran another delta. 2026-04-17T15_00_40.358Z - backup NG.txt

[Pilow]

@acebmxer so, NBD it was...

holy molly, you have some good network performance !
what kind of SR at source ? and remote at destination ?
what about the PIFs ?

[acebmxer]

@Pilow

Just a little old truenas running on AMD 5900x with 10 Gic nics bound, Unifi Agg switch with 10gb links to hosts.

Storage 5 8tb tohisba drives and two 1tb nvme drives 1 for cache 1 for log vdev.

Backup device is a DS1819+ with 4 12 tb seagate exo drives with 10gb link.