"To unmount it just go into the web interface click on disk managment > USB settings and the should be an option "delete usb disk assignment".
PCPiranha--I whole-heartedly agree there should be an option via the browser to "delete" or "unmount" (friendly) an external drive--but there isn't. Cancel button takes user back to top of drive maintenance.
I have a linkstation duo pro, 3.09 firmware, mirrored.
It will backup just fine....but on any reboot (tested again) the drive comes back as unrecognized--it will see the manufacturer (Seagate) but not the data or size or even the file type. I have tried FAT 32 and XFS and neither escaped the problem.
The only way to have it "mount" back successfully (meaning actually see/utilize data, disk size, file type, etc) is to reformat and re-run my backups.......