The other day, I got two drives reporting disabled, disk 15 (4TB) and disk 17 (500GB). I replaced them with an 8TB and another 500GB. They were precleared and then added and were rebuilding and the rebuild finished only to get those two drives disabled again shortly after. I tried rebooting and it came back up disk 15 and 17 still disabled. I also have disk 18 that reported 116068861 errors but didn't get disabled and doesn't have SMART issues reported.

Motherboard is Supermicro H11SSL-i. I ran HD Sentinel on the 4TB and 500GB removed and they tested fine and no SMART issues. The replacement 8TB and 500GB report no SMART issues so I'm taking this to be a motherboard issue or a correct filesystem issue.

Does it look like a filesystem or hardware issue on the motherboard side?

Thanks in advance.

unraid-diagnostics-20260319-2321.zip

Disks were already disabled at boot, so we can't see what happened, but SMART looks fine, and two getting disabled at the same time typically means a power/connection issue.

The syslog in the diagnostics is the RAM version that starts afresh every time the system is booted. You could enable the syslog server (probably with the option to Mirror to Flash set) to get a syslog that survives a reboot so we can see what leads up to the problem which might give a clue as to what is going on. The mirror to flash option is the easiest to set up (and if used the file is then automatically included in any diagnostics), but if you are worried about excessive wear on the flash drive you can put your server's address into the remote server field and log to a share instead.

Probably nothing wrong with those original disks. They were likely just having the same problem the new ones are. Bad connections are much more common than bad disks.

The drive bays were not using a common power connection and it was tricky to change cables for the time being so I just swapped the bays the drives were in and precleared one of the 500GB disks that is reported as disabled. I stopped the array to try and use the 500GB disk again, but it still shows as disabled. In the meantime, another 3TB is now disabled. So the problem follows the drive bay, which is good to know for when I can swap SATA cables tomorrow.

But I do need to get at least one more disk to work to start the array with 2 disabled/rebuilding disks.

Thanks

unraid-diagnostics-20260320-2238.zip

Reboot, start the array in normal (not maintenance) mode, and post new diagnostics.

Back to showing the 8TB and 500GB disks as disabled.

Thanks

unraid-diagnostics-20260321-0124.zip

Both emulated disks are mounting. Assuming the contents look correct, you can rebuild on top, and any further errors, grab the diags before rebooting.

17 minutes ago, JorgeB said:

Both emulated disks are mounting. Assuming the contents look correct, you can rebuild on top, and any further errors, grab the diags before rebooting.

What do you mean by "rebuild on top"?

Thanks!

1 hour ago, CaptainMorganCrunch said:

What do you mean by "rebuild on top"?

That is covered here in the online documentation.

6 hours ago, trurl said:

start the array in normal (not maintenance) mode

4 hours ago, CaptainMorganCrunch said:

Back to showing the 8TB and 500GB disks as disabled.

Didn't expect otherwise

3 hours ago, JorgeB said:

Both emulated disks are mounting

This is what we needed to see before proceeding and couldn't see without the array started. If they were unmountable, more would need to be done before rebuilding.

Server has been rebuilt. Thanks again for everyone's help.