Francis

I've solved it! For anyone else experiencing this issue with an intel 12th gen motherboard - the issue ended up being USB power in the "soft off" (S5) state. For some reason, setting that to OFF prevented the USB port from properly supporting boot-from-usb on the next boot. Re-enabled USB power in soft off and I have had no further issues.

An interesting update - I was able to recover the failed drives and manually reflash them with a backed up image from my servers, and they were able to boot properly. Interestingly, this still occurs regularly, but only on a clean shutdown - when I lost power, the array immediately started back up with no flash drive issues. I then shut down the array normally, and immediately the drive died and could not be used. I wonder if this is possibly something that is happening at the motherboard level? I have used this motherboard and these drives before, but I've never had one plugged in during a planned shutdown. Anyone know of anything that could be killing drives but only during intentional shutdown events?

That's what I'm curious about. One drive I shut down and then it wouldn't boot again, and wouldn't read in my PC. The other drive, I attempted to restart the server, with the same result. I've used this motherboard (and one of the dead flash drives) for another system earlier, so I don't _think_ it's a hardware fault? I wonder if my Unraid image was corrupt somehow that I've been using to install it. Edit: I allowed the array to build fully for the first time, then backed up the flash with the "My Servers" tool and shut down the system. Result: a third flash drive is dead and the server won't boot with it anymore. Sigh. Before using this flash drive, I did a full verification with h2testw and it passed. The error I get on my PC is "request for the usb device descriptor failed."

I have used Unraid with a Sandisk Cruzer USB 2.0 flash drive, as well as a no-name generic flash drive. Both of these work for Unraid, however, as soon as I shut down the server for the first time, the USB drive appears to be permanently corrupted. Windows reports "The USB drive has malfunctioned" and won't even let me view partitions or similar in disk management. I don't really want to plug in a third drive and have it be permanently bricked too. Any suggestions? I know this isn't a server hardware issue, as I have used this motherboard with usb drives before with no issues.