Error light meaning


I’m having issues with the HDDs on my SATA Hat, 4x2TB L200 2.5" drives. I’ve been using ZFS and I get errors with one of the drives and the red LED for that drive lights up on the SATA hat. I’ve swapped the drive between another one and the red LED has followed the drive. However, I can’t find why this drive is throwing an error and what parameters the LED uses to be red or not. What sets this?

Also I found to get ZFS stable I had to use usb-storage rather than UAS. Is there a list of drives that are stable under UAS?

I’m running latest ubuntu 20.04 64 bit and update the SATA Hat firmware yesterday.

All the best,

It would appear the red error light indicates a SMART Error or Warning.