Yeah I know the B&R server basically has one integrated…meant a seperate Linux one.
Then I can confirm that you can do it with Windows without too much fuss. It was definitely a little fiddly to get the permissions such that it was happy, but I haven’t touched it since.
But that support was dropped, wasn’t it?
You might(?) mount ReFS on Windows 11, but there is no longer support?
I think you can no longer format a disk to ReFS on Windows 11, like you were able on Windows 10.
Totally agree, that is my point. Asking if 45 supports ReFS is like asking if they support MS Word.
I guess that ReFS is to be used with direct access to disks and not RAID controllers, just like ZFS.
I would also not do it, if not needed performance wise. I agree that it is not great. But for just one single share and without complicated stuff like AD integration, I think even the not so great Windows implementation should be fine.
Sure? I doubt it, iSCSI+ReFS alone does not really say what is underneath it. Another ReFS? ZFS? ext4?
I think in general it is best to avoid iSCSI if not absolutely needed.
And since SMB works, it should be fine for this use case.
I would set the record size accordingly to what you have set in Veeam.
If want to go above 16TB, you need 4MB.
For a NAS, they recommend:
- 512 KB — select this option for backup to NAS and onsite backup. With this option selected, Veeam Agentwill use data block size of 512 KB. This option reduces the size of an incremental backup file because of reduced data block sizes.
Something else that is pretty interesting, is the compression settings.
LZ4 on Veeam is the default.
But the doc also says about ‘none’:
This compression level is recommended if you plan to store backup files on storage devices that support hardware compression
Which is the case for TrueNAS, I guess, even though it happens in software?
So while you need more bandwidth, it might be that having lz4 only on the ZFS dataset and ‘none’ in Veeam gives you a better result than having it enabled on both. But I guess it does not really matter much.
Not that I’d know of - just checked with my Windows 11 Pro for Workstations VM - I can format a volume ReFS.
Afaik all editions can work with ReFS volumes but only Enterprise and Pro for Workstations can format as ReFS.
I think I even recently read something about Microsoft integrating it into the Windows Setup so you can install directly to ReFS.
ReFS can very much be used on top of a RAID if I understand this documentation correctly.
From your link:
Storage Spaces supports local non-removable direct-attached via BusTypes SATA, SAS, NVME, or attached via HBA (also known as RAID controller in pass-through mode).
The extra mention of HBA mode seems like proof to me, that RAID is not recommended. Typical MS move, calling it pass-through mode, when almost everybody else calls it IT-mode 
You read under “Storage Spaces”, I specifically linked to “Basic Disks” where it says:
Basic disks include local non-removable direct-attached via BusTypes SATA, SAS, NVME, or RAID. Basic disks don’t include Storage Spaces.
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You are technically correct, but as this is the TrueNAS forums I assumed that what I actually meant (a zvol hosted on TrueNAS ZFS, presented to the Windows host via iSCSI and then formatted in ReFS) would be implied.
EDIT: Sorry, if that sounded rude, I didn’t mean it that way. Just wanted to clarify what I had meant.
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I agree with this, I think iSCSI still doesn’t transmit sync write requests? So you have to set sync=always to safely use it with zfs and that’s butts unless you have a good SLOG.
I did a bunch of testing with this on my own stuff and found the TrueNAS compression (even ZSTD) to be inferior to the Veeam compression.
Do your own tests, but for me the most effective setup was Veeam compression at the highest level that the performance was acceptable for you and leave TrueNAS with the default LZ4 compression for metadata compression on ZFS. YMMV.
I mean, it is the exact same compression if you use normal 
Probably also pretty good since you compress with zstd on Veeam and compress the zeros with lz4. But I guess if you would get the same result by enabling zsdt 9 or even higher on TrueNAS
The results just weren’t as good from the truenas even at comparable compression levels for me. As I said, your mileage may vary and I recommend you do your own tests.
Also, when you look at my results, keep in mind that I’m using a base spec X10 and my veeam server has a ton of cores and RAM. I have compute and memory to spare on the Veeam side but limited computer/RAM/storage on the truenas side.
There’s a method to my madness, and it might just be madness to you if your variables aren’t the same as mine.
I’d be interested in seeing those test results. Might be that they have a newer version of zstd vs what we have, and there’s more moving parts in play with ZFS than just “hey bump up the version on the package”
Oh, also this was now like 2-3 years ago I did these tests. I’ll see if I still have that notebook, I may have already tossed it in the work shredder. 
EDIT: Also the differences weren’t HUGE, like 5% max. Our pool is small, so I was looking for any advantage I could get.
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We might indeed have changed things, but if you’re getting good results then stick with it. Odds are you’re able to work with bigger block and dictionary sizes if Veeam is doing the compression, so that’s where the 5% win is coming in.
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