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Comment by terrywang | Hacker News Reader

Btrfs is flexible and works well for self-hosted home storage use cases, especially running cheap hardware & HDDs with mixed RPM + capacity specs (many consider it a major advantage over OpenZFS on Linux which inherits ZFS pros and cons). As far as data corruption is concerned, avoid using raid{5,6} profile (that governs how a chunk is replicated within or across a member device) for data and you should be fine.

Running OpenZFS on Linux also requires dealing with DKM(ES)S, Ubuntu being an exception (hmm)...

NOTE: Self-hosted podcast show episode 25 contains excellent coverage (ZFS vs. Btrfs) by Jonathan Panozzo from Unraid.

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I've used ZFS on FreeBSD for many years and it's absolutely rock solid. There was even a case where an IPMI had been hacked and the attacker reformatted the disks for Windows 10 and I was able to recover most of the the data. The attack was interrupted before they could copy data to the disk and I had left a small amount of space unallocated at the end of the disk.

Lessons learned:

- ZFS is very robust for handling partial corruption

- Always leave unallocated (~1gb) space before and after critical data partitions. accidental/malicious reformatting will likely use the entire disk so the new FS superblocks are less likely to overwrite all of the original ones.

- Always have an offline backup of your partition table in case of accitental/malicious repartitioning

The one thing that still makes me nervous is large stripes of mirrors where a multi-disk failure in one mirror can take out the entire stripe. For that reason I stick with simple 2 disk (or 3 disk for critical data) mirrors and avoid combining them in stripes.

Yes, canonical was brave enough to assume they don't need DKMS for zfs.ko ... [1]

From my experience, Ubuntu's ZFS support is pretty solid, even for root disks. There were some limitations in the past, however - for example, you might not want to use ZFS on a ssd root because of its write amplification.

By the way, there's a handy PPA with newer versions [2] - but this does use DKMS.

[1] https://ubuntu.com/blog/zfs-licensing-and-linux

[2] https://launchpad.net/~jonathonf/+archive/ubuntu/zfs

I use ZFS on my main computer, but it sends its backups to a tiny computer with two laptop USB drives plugged in, running Btrfs RAID-0. (The second drive was added when the first one filled up.) I did it that way because it's the second copy of the data, and I'll only need to call on it if my main computer dies. I have a sentry program running on the tiny computer that regularly checks that all the data is present, correct, and readable. The likelihood that it breaks at the same time as my main computer is slim.

I wouldn't trust Btrfs for much more than that.

I specified ZFS for some of work's very large servers (>100 drives). They wanted to do hardware RAID and XFS instead, and I can just image the nightmares that would have involved.

What is kind of neat for your case maybe is that you can run btrfs scrub even on raid0 or a single drive. The scrub command reads the whole filesystem and verifies checksums, so you can be sure that the data is readable and correct.

Disclaimer: I only tried it on a single disk.

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