On Mon, Jul 21, 2014 at 08:17:19PM +1200, Peter Kane wrote: > Hello > > I have run into another strange problem on the Optiplex 745 in the > dmesg below. It usually boots with a usb crypto key disk, but if I try > to boot with a particular usb hard disk attached it will fail to find > the key disk and will instead erase the disklabel on the usb hdd. The > data is all OK if the disklabel is restored from file. > > The external disk in question is a 3 terabyte Seagate Expansion Desk > unit (see end of dmesg). I tried another external hdd but it didn't > suffer the same problem, and the Seagate wasn't wiped on other crypto > machines that I tried it with.
The boot loader searches disks presented by the BIOS for disklabels and softraid meta data. If the bootloader can't find the keydisk while the external 3TB unit is plugged in, then I'd suspect a problem in the way the BIOS handles this particular disk. You can run 'machine diskinfo' at the boot> prompt to see how the BIOS presents disks to the boot loader. It's worth noting that Seagate's product page says 3TB volumes use 4K sectors: http://knowledge.seagate.com/articles/en_US/FAQ/005486en?language=en_US I'm not sure why the disklabel on the 3TB volume ends up being deleted...
