I have recently been experiencing some anomalous behavior in regards to the interaction between my external hard drive and my OS. Hopefully someone will recognize this problem. In any case, some background:
I am running Ubuntu 10.04.3 LTS with Gnome 2.30.2 and a 2.6.32-37-generic kernel on an Inspiron 1525. The external drive is a Western Digital WD6400AAV, which, for the purposes of troubleshooting, has been taken off a LAN and connected to the laptop via a Gigaware USB hub.
Under normal conditions, when I open the disk utility (gnome-disk-utility 2.30.1-1) with no other external media mounted, the drive would appear as /dev/sdb with the following three partitions:
- Partition 1 - /dev/sdb1 (a 133GB FAT volume used as a network share, mounted at /media/example1)
- Partition 2 - /dev/sdb2 (a 253GB ext4 volume used to back up my /home, mounted at /media/example2)
- Partition 3 - /dev/sdb3 (a 253GB ext4 volume used to back up my wife's /home, mounted at /media/example3)
Mounting and managing the partitions from the GUI disk utility is straightforward and trouble-free.
Under current conditions, when I open the disk utility with no other external media mounted, the drive appears five discrete physical volumes, enumerated as follows:
- /dev/mapper/1WD_6400AAV_External-part1 ( 133GB FAT mounted at /media/example1)
- /dev/mapper/1WD_6400AAV_External-part2 ( 253GB ext4 mounted at /media/example2)
- /dev/mapper/1WD_6400AAV_External-part2 ( 253GB ext4 mounted at /media/example3)
- /dev/mapper/1WD_6400AAV_External ( 640GB of unallocated space, no mount point)
- /dev/sde (as per the paragraph above, with /dev/sdb1..2..3 now /dev/sde1..2..3 and not mountable, i.e.: error:device already mounted or busy)
From the desktop taskbar, the Places contextual menu lists each of the three partitions twice. By way of example, clicking on example1(the first volume listed) will bring up a nautilus window for the partition, clicking on example1(the second volume listed) will result in a (error drive not mounted) message.
Attempts to unmount /dev/mapper/1WD_6400AAV_External-part1(-through-3) and /media/example1(-though-3) from the GUI as well as from a privileged terminal resulted in actually unmounting the respective partitions (and this fact was indicated in the GUI representations of the “discrete physical volumes”), but did not alter the error message when any attempt to mount or manipulate the GUI representations of the /dev/sde1-3 “volume”. Attempts to delete any partitions/volumes from the GUI disk utility gave an error indicating a block device was holding the volume.
So, other steps taken thus far:
- Booted into Gparted from a Multisystem USB drive. Removed all partitions from the Western Digital. Wrote zeros to the entire 640GB volume with time dd if=/dev/zero of=/dev/sd(whatever). Recreated partitions. Hoped no disaster struck while back-ups temporarily nonexistent. Rebooted into Ubuntu... no change, GUI still screwy.
- Next, acting on a late breaking brainstorm, I connected the WD to my wife's laptop and started the disk utility. Everything normal. No problems here. Hummmm.
- Reinstalled gnome-disk-utility on my laptop. Reconnect the WD. Anomaly intact.
- Realizing that while I update daily, my wife's system usually only gets updated when I remember to do it. I check, and sure enough, 218MB worth of updates stacked up. Could the problem be some update breakage? One big update later, her machine still exhibits normal behavior while mine still... doesn't.
Having recreated my back-ups, I am now retiring with a drink and my copy of Understanding the Linux Kernel to read up on block devices. I would sincerely appreciate any input in running down the source of the problem.
