It happened to me too (third time...) on my testserver, HP DL120 G7.
This one is running on 2 x 4TB drives.
Another one runs on smaller < 2Tb drives, no problems yet.
Any hint on what is the cause? Or how to create a boot USB to get it on its feet again?
Suffering from the same (using a usb serial adapter to readout some smartmeter) I created a workaround:
Either Logwatch for the above and then perform a reset/reload of the USB.
Google for billauer.co.il usb-reset-ehci-uhci-linux
Or cron it every 5 minutes...
Works for me...