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Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by m0zg on Monday July 20, 2020 @07:25AM (#23896744)
> ZFS is fine, but it is overkill for most home applications

Yeah, not having silent data corruption is "overkill", sure. /s Why not use ZFS? It takes 15 seconds to install, and its CLI is fairly intuitive. Works fine. Costs $0. Why not, even for "home" applications?

I could see how it could be unsuitable for "entreprise" applications where there are strict performance requirements etc, but for home, I wish I could use ZFS everywhere.

Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by StavrosK on Monday July 20, 2020 @08:39AM (#23897142)
For one, because of the fact that you can't add an extra disk to your pool if you need to. GP is saying "plan better", no need to get snarky.
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by magnetic on Monday July 20, 2020 @10:09AM (#23898001)
What do you mean? I've done this not so long ago on my pool.

https://unix.stackexchange.com/questions/530968/adding-disks...

Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by StavrosK on Monday July 20, 2020 @10:17AM (#23898083)
You can't add disks to a vdev, though, which is what most people with a home NAS (including me) want.
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by trasz on Monday July 20, 2020 @12:34PM (#23899447)
You can add them to RAID0/1 vdevs; you can't add them to RAIDZ vdevs. Which you don't have if you don't run ZFS. You might have RAID5, but then you also have a write hole.
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by pantaloony on Monday July 20, 2020 @11:20AM (#23898665)
Strongly disagree that the CLI is intuitive. It’s very easy to kick off unintended actions or back oneself into a corner while doing things that seem reasonable. It’s like using Git in that it’s very hard to do well without a good understanding of the fundamentals, which feel almost nothing like managing disks normally. Lots of things require multiple steps that aren’t obviously related and you’d better not screw them up.

It’s way at the far end of the “must RTFM to use safely, and then probably brush up on it again before actually doing anything unless you use it daily” spectrum of intuitiveness.

I like my ZFS mass storage volumes for my home server. I worry I’ll screw them up and/or burn an hour googling and reading the manual every time I have to touch them, though.

Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by briffle on Monday July 20, 2020 @10:50AM (#23898370)
or install BTRFS and be able to detect bitrot as well, but also be able to grow your storage by adding more disks. (even different sizes)
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by Mister_Snuggles on Monday July 20, 2020 @11:22AM (#23898687)
I've been burned by BTRFS too many times to trust it.

At work, our servers will get into a state where they just hang for a span from minutes to hours while BTRFS does "something". I'm not one of the admins though, so I don't know the exact details. I just know that this is a vendor-supported configuration and the vendor has been unable to tell us why this happens or offer any solution that makes it not happen. Our answer to this issue has been to rebuild servers with ext4 when things get bad. This has happened on multiple servers hosting different applications - the only commonality seems to be that write-heavy loads get it into this state. Servers that just have their OS on BTRFS but do all of their work on NFS volumes are fine.

At home, I once rebooted my OpenSuse Tumbleweed laptop and ended up with a BTRFS filesystem that couldn't be mounted RW. Fortunately I was able to mount it RO after booting off installation media and copy my data off, but I couldn't get the filesystem back into a state where it could be mounted RW. I ended up reinstalling. I never did figure out the root cause, but I suspect that some BTRFS-related process was running when I rebooted.

On the flip side, ZFS has never let me down in this way, but to be fair I've never subjected it to the same use-cases. Unfortunately, the inability to resize/reshape the filesystem is an issue for me. I believe that it's being worked on, but I don't think that work is production-ready yet.

Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by tw04 on Monday July 20, 2020 @11:37AM (#23898851)
RAID-Z expansion is being worked on: https://github.com/openzfs/zfs/pull/8853

Last I checked BTRFS RAID5/6 was a dumpster fire and unusable in production. Have they actually open sourced the ability to fix bitrot detection with mdraid? If not, it's kind of irrelevant.

So... once again down votes without response - BTRFS raid still isn't recommended and the file healing isn't compatible with MDRAID I assume and you just don't like the fact I pointed it out? The "I'm downvoting because you pointed out a flaw in my logic" @HN is disappointing.

Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by accelbred on Monday July 20, 2020 @04:25PM (#23901530)
If you're using RAID-Z on zfs, your comparison isn't fair. Rather than use RAID56 with btrfs, the equivalent would be to get 1 or 2 disk redundancy with raid1 or raid1c3.
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by tw04 on Tuesday July 21, 2020 @10:16AM (#23906935)
RAID-Z is the equivalent of RAID-5. RAID-Z2 is the equivalent of RAID-6. RAID-Z3 would be the equivalent of RAID-7 (or whatever the standard is named for 3-disk parity).

This is strictly speaking to how it deals with data and parity, the implementations are obviously different.

RAID-1 would be a mirror in ZFS parlance.

Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by accelbred on Thursday July 23, 2020 @02:26AM (#23924706)
BTRFS raid1 isn't mirroring drives though, it means there are two copies of each extent across the whole set of 2+ drives. and BTRFS and raid1c3 and raid1c4 are 3 and 4 copies.
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by trasz on Monday July 20, 2020 @08:19PM (#23903226)
Not really - RAIDZ is basically RAID5 without the write hole problem. ZFS equivalent to RAID1 is called 'mirror', and is... well, a mirror.
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by accelbred on Thursday July 23, 2020 @02:28AM (#23924719)
Yes, and btrfs's raid1 isn't a mirror. Btrfs's raid1c3 and raid1c4 are its alternative to raid5/6 without the write hole.
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by trasz on Friday July 24, 2020 @06:02PM (#23944947)
No, it's still a mirror, just spread over more than two devices. Size overhead is still that of a mirror, ie quite a bit higher than that of raidz.
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by Geezus_42 on Monday July 20, 2020 @11:08AM (#23898553)
Just avoid RAID 5/6...
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by Geezus_42 on Monday July 20, 2020 @06:01PM (#23902352)
Just avoid RAID 5/6
Re:In Praise of ZFS on Linux's ZED 'ZFS Event Daemon' by paulie_a on Monday July 20, 2020 @08:01AM (#23896905)
If it's cli it's a nonstarter

Even if it has a gui it's probably a non starter unless there are literally 2 options