Is it because USB doesn’t expose proper UUIDs or something?
Comment on Just a bunch of enclosures
emptiestplace@lemmy.ml 7 months ago
Oh no.
Unfortunately I have a lot of experience with this: attaching permanent array members via USB is a bad idea. OP, if it’s not too late, and assuming you haven’t already and decided to double down on yolo, I’d recommend reading about the downsides of this approach. It is easy to find relevant discussions (and catastrophes) in r/zfs.
Thunderbolt enclosures are a bit more expensive, but they won’t periodically fuck up your shit just because.
MangoPenguin@lemmy.blahaj.zone 7 months ago
seaQueue@lemmy.world 7 months ago
Bus issues usually. Having a disk (or 4) drop out of a ZFS filesystem regularly isn’t a good time.
If you can find a combination of ports on the machine that doesn’t have bus issues you’re usually fine (assuming the enclosure is reliable and doesn’t have driver or firmware issues.)
lightrush@lemmy.ca 7 months ago
ASMedia ASM1351 (heatsinked) or ASM235CM on the device side 🥹
Shimitar@feddit.it 7 months ago
Been on USB enclosures using Linux software raid for 20 years and never lost a bit so far.
Didn’t go cheap with USB jbod, and i have no idea if zfs is more sensitive to USB… But I don’t use zfs either so don’t know.
But again I have been using two jbods over USB:
- 4 SSDS 2+2 RAID1 on usb3
- 2 HDDs on RAID1 ON USBC
All three raid are managed by Linux software raid stack.
The original one I think I started in the 2000’s, then upgraded disks many times and slowly moving to ssds to lower heat production and power usage.
Keep them COOL that’s important.
emptiestplace@lemmy.ml 7 months ago
What an assertion - if you’re not using ZFS, how do you know you’ve “never lost a bit so far”?
lightrush@lemmy.ca 7 months ago
I’ve been on the USB train since 2019. You’re exactly right, you gotta get devices with good USB-to-SATA chipsets, and you gotta keep them cool. From all my testing I’ve discovered that:
- ASM1351 and ASM235CM are generally problem-free, but the former needs passive cooling if close to a disk. A small heatsink adhered with standard double-sided heat conductive tape is good enough.
- Host controllers matter too. Intel is generally problem-free. So is VIA. AMD has some issues on the CPU side on some models which are still not fully solved.
I like this box in particular because it uses a very straightforward design. It’s got 4x ASM235CM with cooling connected to a VIA hub. It’s got a built-in power supply, fan, it even comes with good cables. It fixes a lot of the system variables to known good values. You’re left with connecting it to a good USB host controller.
skittlebrau@lemmy.world 7 months ago
I imagine if someone had to do it this way for whatever reason, Thunderbolt would be more reliable? Assuming it’s true Thunderbolt using a SATA bridge?
emptiestplace@lemmy.ml 7 months ago
Yes - and unless you treat each enclosure as its own failure domain, it will still be a compromise, but it’s a lot better.
lightrush@lemmy.ca 7 months ago
Thanks for the warning ⚠️🙏
This isn’t my first rodeo with ZFS on USB. I’ve been running USB for a few years now. Recently I ran this particular box through a battery of tests and I’m reasonably confident that with my particular set of hardware it’ll be fine. It passed everything I threw at it, once connected to a good port on my machine. But you’re generally right and as you can see I discussed that in the testing thread, and I encountered some issues that I managed to solve. If you think I’ve missed something specific - let me know! 😊