Hey, I’m really stumped by this issue so perhaps one of you folks might be able to help me out here. I run a little server on an RPi 5.i got for another project originally. So ce I cannot finish said project due to time constraints, I repurposed the thing into a little server. It’s running smoothly so far with one really weird exception. Whenever I attach more than 1 HDDs to the pi and use at least 2 at the same time, both HDDs will start to fail, unmount and the whole USB hubs I connected them to will just disappear from LSUSB. Originally I thought this was a power issue but the weird behavior continues when I connect each HDD to it’s own powered USB hub. I’m really at a loss as to what’s happening. Any ideas?
Suggest the typical hardware device troubleshooting. watch/tail your dmesg -w or kernel log as you add the extra drive. It’s curious that the system itself doesn’t crash, but from your description it still sounds like a power starvation concern or possibly high temperatures if this device is under heavy load.