ZFS or BTRFS as the best way to setup a dedicated urbackup server?

Old xeon server, 4 cores, 8GB ram, 2x 500GB hdd

maybe some budget to add SSD if there is a serious advantage in adding a caching device to speed up de-duplication as described in freeBSD section in documentation.

from all the possibilities to setup urback I believe it comes down to

  • Linux + btrfs
  • freeBSD + ZFS

I am unsure which should be my main focus. ZFS is more robust, but maybe my RAM is not enough.
Or maybe btrfs in 2018 is solid enough to just work.

Searching forum, theres talk about deduplication on ZFS being better.
But theres also talk about btrfs and: “integrated snapshot management with UrBackup able to make forever incremental (synthetic backup)”

UrBackup has the benefit of "integrated snapshot management with UrBackup able to make forever incremental (synthetic backup)” with ZFS as well.

I run a few UrBackup servers with ZFS as the underlying storage and it works tremendously well! I chose not to go the btrfs route because Redhat pulled their support for btrfs which does not bode well. I am not saying it won’t be a great file system, I would just like to see more development behind it before I turn my backup system loose.

Be aware, there are bugs in ZFS, specifically regarding replication, that may cause you issues, but they do not affect the normal operation of UrBackup at all.

Regarding your system, you are light on RAM if you are considering features like dedup in either system. Those features eat tons of RAM.

I’d go with btrfs. But maybe you already have existing Linux or FreeBSD knowledge, then you can go with whatever you are more comfortable with.

Btrfs is mainly unsuited if you have more than two disks (RAID5/6).

SuSE offcialy supports btrfs and they have a few developers working and fixing bugs on it. But yeah, ZFS is a bit more solid (on FreeBSD; the last ZFS on Linux version had a pretty serious issue).

“Btrfs is mainly unsuited if you have more than two disks (RAID5/6).”
Hello, this conclusion is correct? Btrfs is not suitable for more than 2 disks? If this is the case, if btrfs is selected, only a single hard disk can be used.
@uroni @orogor @chanceellis

My English is not good. Do I understand it wrong?

I’m sorry, I understand. He said that raid5/6 refers to the functions of Btrfs file system, not raid5/6…

I used to use centos1708+btrfs, very stable, function normal, but the mount function is not normal, now change to ubuntu+btrfs, LSI8260-8i RAID equipment

OP here
So, just yesterday I put arch linux on a usb stick from which the system boots
and the two 500GB drives are mounted just for pure backup storage, btrfs raid0
mounted in fstab with these flags:
defaults,compress=zstd,noatime,autodefrag,subvol=@

will be running this setup and see how it goes and behaves.