I would like to ask whether Turris Omnia supports ZFS pools. I would like to use in NAS box ZFS pool (2 disks in mirror) from my existing NAS.
Yeah, I wish I could run the same system and tooling on Omnia as I do at all the systems at work and feel a bit safer about my NAS data.
It’s my understanding though that you’d have to build OpenWRT with ZFS support yourself and also make sure to dedicate large amounts of RAM to ARC for it to even make sense (here’s where the 2 GB would disappear easily).
I would advice against that.
-Only 1/2GB of RAM.
-No ECC Ram.
—> Not very good for ZFS.
btrfs provide almost same features and is supported
I’m sure it’s fine on a router like this, it’s just that we have been running ZFS on petabytes of production data for over 10 years and kind of trust it (and not BTRFS). Not enough RAM and lack of ECC are the killers though.
I’m running my zfs testing on Omnia for a year or so. There are much more other problems than 1/2GB ram.
First of all Omnia is 32bit, which is a big problem on Linux/ZFS. It is problem how 32bit Linux kernel allows virtual memory allocation under kernel mode. This was the main issue I had when I work on the port.
Second Omnia is based on LEDE which uses musl libc and compiling zfs tools was a pain against it. I did not have the time to port that so I created small base gentoo chroot (I call that buildroot alternative) with zfs tools and glibc. But the usage was pretty restricted because of the first problem and the pain of changing kernel command line (it is hardcoded in uboot).
So for “production” usage I abandon this and stayed on my homemade freebsd zfs appliance.
I want to get back to this in short time, since many things changed mainly in ZFS trunk and 32bit status is now much better.
I dont agree that 1GB ram and non ECC is such a big issue. It depends on what you want to do there. For something like backup appliance or small home NAS it is enough. In work I run small Rpi3 (64bit, 1GB) ZFS backup appliance with 500GB RAIDz1 pool. It is place for my incremental backups and runs very well, biggest bottleneck here is the 100Mbit lan chip on Rpi3. This appliance based on Gentoo has root on ZFS with beadm, etc. Hopefully I will find a time to create wiki page on Gentoo wiki to document that (I did not found any such solution yet).
Having not ECC is an issue for all the filesystems and storage, so it would be the same issue if you use btrfs or ext4. If you have concern just create another backup appliance for the most sensitive data (the Rpi serve as the backup of the backup, cheap and good enough).
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Still did not have much time to get back to Omnia & ZFS (my buildroot somehow broke and forgot to create a snapshot, why the hell when I use ZFS).
But started to edit wiki about general root on ZFS with all its goodies.
thanks a lot for sharing this info. I guess i won’t use my omnia as a NAS then.
Agree, have been running ZFS for 10years now mostly with 4GB or less RAM. And when it comes to ECC RAM, it’s important to know that ZFS was designed to run without it. So it’s perfectly fine to use normal RAM. However for maximum data integrity ECC RAM is a must, with any filesystem.