I see that the documentation states that our backup server should be saving to NTFS. Is that up to date? It looks like there has been some work done on backing up ReFS volumes. I’m hoping to move my urbackup data store to a ReFS volume if possible.
Yeah, it works with ReFS (v3) now. If you decide to use it please provide some feedback? (E.g. report about performance and storage efficiency).
The problem is ReFS reflinks (which UrBackup uses) don’t work efficiently with Windows Server Dedup. So there is no way to compress (or deduplicate) files with ReFS. As a result I can’t really recommend this setup over NTFS. Meanwhile the best OS + file system for UrBackup is still Linux with btrfs (maybe that’ll be usable on Windows with WSL2 
).
Hi uroni, thank you for your reply. I am guessing that reflinks are only used for file backups, correct? I only do image backups with urbackup. I’m sure you’ve learned this already but I will state the obvious: it works amazingly well! 
I may move to Linux but we use Microsoft Action Pack and get a lot of perks, like Server OS licenses. MS dedup works very well but does have a big performance impact on restores. I plan to move to ReFS, and enable OS compression. Then I will test a restore, then enable deduplication and test restore speed again.
I will report back!
The advantage of ReFS would be that you can do CoW-Raw image backups but those don’t interact well with dedup. If you are using vhd/vhdz you might es well just use NTFS (more stable).
Thank you uroni, that makes sense.