I got the above error for fix common problems and was prompted to post my diagnostics here.

I installed a new ssd to create a cache pool several weeks ago and while the ssd always ran hot even when idle (40-50 C) it didn't seem to be a concern.

Checking the logs it looks like there are BTRFs errors and I'm not sure if it's a failing drive, or something I might have done setting up the cache pool but this is the first I'm getting this error and it looks like it's been the past few days.

I'm not sure if I've diagnosed this drive correctly as the problem or next steps with using Scrub since this thread seems to have a lot of cautions (https://www.reddit.com/r/unRAID/comments/qbwoa8/how_do_i_get_rid_of_the_btrfs_error_device_sde1/). I think I want to know

1) Is the drive dying/bad

2) Steps to not have my cache data corrupted/revert back to the single SSD if the 2nd is failing.

I don't want to do anything too stupid and hope someone who knows more than I do can point me in the right direction.

Thanks!

tower-diagnostics-20250928-0925.zip

One of the pool devices dropped dogflince, reboot/power cycle to see if it comes back and post new diags after array start.

Thanks for your response!

I ended up removing the drive and trying to run a SMART extended test but couldn't get that to work. I ended up reformatting and adding back to the cache pool and was able to run a SMART extended test there. It came back with no errors. Not sure why the drive would have dropped, but at least according to the SMART test the drive is fine. As a side note, the drive runs consistently "warmer" at ~40-50 celsius while idle if that means anything. I've attached the diagnostics. If you could, let me know if I should be concerned about anything or if I should just wait to see if I get more errors in the future. Thanks!

tower-diagnostics-20251002-1753.zip

Keep monitoring the pool for now. I recommend installing this script https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/2/#findComment-700582