New server, need advice

Greetings. First of all, i would like to thank for this great software. I have been testing with different server/client configurations to see if this is the product that i need, and it suits almost all my needs at the moment. I will use it mostly for internet backups, and i have the following to use as server:
i5 8400 - 32gb ram - 3x 8tb sata drives (with room for other 3) and an m2 ssd for OS.
I was thinking of using debian or ubuntu with ZFS raidz1, but my fear is that 32gb of no ecc ram will not be enough. The server will be for about 100 clients doing mostly file incrementals during the night.
It is very likely that in the future it ill have other 3x8tb discs and maybe more ram, but say in a year or so.
Another safer option is mdadm raid5 now and raid50 later, but i would really like to have some of the features of zfs.
Any thoughts?

I’ve had bad experciences with ZFSOnLinux and a high load (hung itself up in the order of a day or two of operation). It worked better with FreeBSD/FreeNAS, so I’d recommend using that instead (hung itself up only every other week or so :wink: ).

If you are okay with RAID10, I’d recommend btrfs with a 4.19.x kernel and some patches (see

Not using ECC RAM is a bit of a risk. If you get a bit error it can be extremely annoying to diagnose the issue and it can obviously corrupt your file system.

If the server can handle 100 client depends on the number of files/changed data each client has per backup.

I have been using Ubuntu 18.04 + Urbackup + ZFS for a “long” time. Stability is good, the only problem was when there was a lack of RAM.

For you is 32GB ECC fine - i think :slight_smile:

My setup:
4x8TB RAID 10 / mdadm
2x8TB RAID 1 / mdadm

The problem I know about:
-Urbackup + ZFS does not support virtual clients
-not working with Ubuntu 20.04

uname -a
Linux **** 4.15.0-62-generic #69-Ubuntu SMP Wed Sep 4 20:55:53 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

UrBackup/clients# ls -l | wc -l

zpool list
pool-**** 21.6T 18.1T 3.49T - 31% 83% 1.00x ONLINE -

uname -a
Linux **** 5.0.0-37-generic #40~18.04.1-Ubuntu SMP Thu Nov 14 12:06:39 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

zpool list
**** 18T 14.9T 3.13T - 6% 82% 1.00x ONLINE -

I have evil experience with BTRFS, never more…

Thank you @uroni for your thoughts. Sadly, any form of mirroring is not an option due to space requirements. My only concern with the freebsd/freenas alternative is having a bottleneck somehow with ram or the discs. I will investigate this further.

Thank you @RoBoSK for sharing your experience. How much ram do you have with the 21.6T pool?

16GB but it is already small, will be 32GB (40GB)

edit: last uptime is ±34 days, only RAM is reason for reboot

I see, thank you again @RoBoSK for sharing!