[SOLVED] zfs error: "cannot receive incremental stream: destination space X quota exceeded."

[kcpx]

Hi everyone,

I have my Proxmox system running fine so far, but recently a problem appeared with my backup strategy.
The whole system is running on zfs and in regular intervals, I create a snapshot of my pool and send it to an external disk with
> zfs send -R -i mypool@oldsnapshot mypool@newsnapshot | zfs recv externaldisk/mypool

This was working fine until now and synced all VMs to the external disk.
Recently, I resized the bootdisk of a VM (from 20GB to 100GB) because space was getting low.
Now, I'm confronted with a strange error when trying to sync to the backup disk:
> cannot receive incremental stream: destination externaldisk/mypool/VMs/subvol-101-disk-0 space quota exceeded.

When I do a "zfs list", I can see the available space on the source subvol-101-disk-0 is 100G, while on the destination it's 20G.
Anyhow, I didn't set any quota for the filesystems so I'm not sure how to proceed.
I think this might be the same problem as in https://redmine.ixsystems.com/issues/26929 , and while it's commented as "not a bug" in that thread, a solution for the original problem is missing.

Can anybody shed some light on this and tell me how to fix this problem?

 

[aaron]

Most likely because the volume dataset on the external disk still has a "volsize" property of 20G. You could remove the dataset on the external disk and send it anew or try to set the volsize property to 100G as well.

zfs set volsize=100G /<pool>/<dataset>

 

[kcpx]

So I tried to set the volsize, but that didn't work out:

> zfs get volsize externaldisk/mypool/VMs/subvol-101-disk-0
NAME                                            PROPERTY  VALUE    SOURCE

> zfs set volsize=100GiB externaldisk/mypool/VMs/subvol-101-disk-0
cannot set property for 'externaldisk/mypool/VMs/subvol-101-disk-0': 'volsize' does not apply to datasets of this type

> zfs get type externaldisk/mypool/VMs/subvol-101-disk-0
NAME                                            PROPERTY  VALUE       SOURCE
externaldisk/mypool/VMs/subvol-101-disk-0  type      filesystem  -

Removing the whole dataset from external disk and sending it again would be an option, but I have some snapshots on that disk that I already removed from the source. So I would rather take that option as a last resort. Are there any other options?

 

[aaron]

Sorry! I missed the subvol. Container datasets are a bit different.

The property should be "refquota".

You can check the current values by running zfs get refquota pool/dataset

 

[kcpx]

Yes, that did it!

Thanks a lot for your help