Today was UPS battery swap-out day, and when I powered my system back up, one of my 3 shucked WD drives was no longer detected by my server by my 4 bay USB enclosure. I pulled all 3 drives and put them into their original WD Easy store enclosures, and again only 2 of the 3 drives were detected (this time by my laptop, not the server). When looking at lsblk, the problem drive is reading as 0 GB and was not spinning up on connection, whereas the other two drives immediately spun up when I plugged them in via USB to my laptop.
The strange thing is that when I installed the non-functioning drive in my gaming tower it spun up and was immediately detected, with data accessible. A few power cycles confirmed it would keep spinning up. Smartctl does not show any red flags and the short test passes without issue. However, it still does not spin up over USB.
Does anyone have any ideas about what might be going on? The drive is 5 years old, so failure isn't unlikely, but it's confusing that it works in the desktop. I'm not concerned about data loss at this point, I have backups and it's a parity drive for SnapRAID anyways. And to get ahead of things, I agree that USB is not the way, but sometimes it's what you have, can afford, and has been reliable for 7 years.
Thanks for your time!