What do you mean by USB hard drive enclosures? Are you limiting the RAID (8 bay) throughput by a single USB line?! That's like towing a ferrari with a bicycle.
I have one enclosure plugged into a USB 3.0 line, another plugged into a "super speed" line, and one plugged into a Thunderbolt line (shared with my 10GbE Thunderbolt card with a 2x20 gigabit splitter).
This was deliberate, each is actually on a separate USB controller. Assuming I'm bottlenecked by the slowest, I'm limited to 5 gigabits per RAID, but for spinners that's really not that bad.
ETA: It's just a soft RAID with ZFS, I set up each 8-bay enclosure with its own RAIDZ2, and then glued all three together into one big pool mounted at `/tank`. I had to do a bit of systemd chicanery with NixOS to make sure it mounted after the USB stuff started, but that was like ten lines of config I do exactly once, so it wasn't a big deal.
Have you researched the USB-SATA bridge chips in the enclosures? Reliability of those chips/drivers on Linux used to be very questionable a few years ago when I looked around. Not sure if the situation has improved recently given the popularity of NAS devices.
So each enclosure hosts its own RAIDZ2. Have you tested if it can survive loss of USB connectivity? It can happen because of cable damage or movement, and also because of any failure in the enclosure's electronics.
unknown|6 months ago
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tombert|6 months ago
I have one enclosure plugged into a USB 3.0 line, another plugged into a "super speed" line, and one plugged into a Thunderbolt line (shared with my 10GbE Thunderbolt card with a 2x20 gigabit splitter).
This was deliberate, each is actually on a separate USB controller. Assuming I'm bottlenecked by the slowest, I'm limited to 5 gigabits per RAID, but for spinners that's really not that bad.
ETA: It's just a soft RAID with ZFS, I set up each 8-bay enclosure with its own RAIDZ2, and then glued all three together into one big pool mounted at `/tank`. I had to do a bit of systemd chicanery with NixOS to make sure it mounted after the USB stuff started, but that was like ten lines of config I do exactly once, so it wasn't a big deal.
YurgenJurgensen|6 months ago
riobard|6 months ago
jimis|6 months ago