Backup of large VM with 23TB fails over SMB - SMB limitation?

[blublub]

Hi

I am trying Veeam and want to backup our large VM which has 23TB and one VHDX file with 21TB - the job always aborts with "not enough free space on target" when it reaches 16TB of copied data.
The network share still has 16TB of free space.

target:
QNAP NAS newest FW over 10GB connection

Is that some kind of SMB limitation I am running into or need i file bug report?
kind regards

[Gostev]

This sounds more like QNAP limitation around the file size or something along these lines, as honestly your VM is nothing special in terms of its size (as 10x bigger VMs are not uncommon in our Enterprise customers). I would try doing a test backup to a different target to see if QNAP is indeed the culprit here. Thanks!

[tsightler]

Is there any change that QNAP is still using ext4 filesystem these days? If so, I believe, at least on older QNAP systems, that they defaulted to 4K blocks for ext4 which supports a maximum file size of 16TB. Just something to look into, I haven't really done anything with QNAP in many years but I feel like I remember reading that they added XFS support some years ago and who knows, maybe that's the default these days, but thought it was worth mentioning since I remember the ext4 issue coming up a few times in years past.

[NightBird]

and over SMB... really not best practice with this crapy devices...

[soncscy]

For sure QNAP (and most NAS vendors) are using EXT4, and that must be the issue. Triple-check the LUN provisioning on the backend, and if you have ext4, it certainly is 4k blocksize.

QNAP, Synology, etc, devices are __not__ performant for modern backups. You hit limitations __very__ fast with the built in file systems, and furthermore, I've hit wonky issue with passing NTFS based USB drives on the NAS USB ports due to what I can only assume are NTFS-3G limitations.

Skip these low-end NAS devices for everything but your lowest end servers. The money spent on a proper server + a bit of training will save you tons of time in the long run.

My advice to my clients is always "if you need to backup Office docs, get a prebuilt NAS. If you need to backup virtual machines, use one of many guides for prebuilt repos."