Seem to be having trouble with mounting a disk partition. It is important to say that this happens only occasionally, i.e. every few days, and resolves itself after a few reboots.
I keep all data files on a separate partition /dev/sda6 which is mounted on /data. From /etc/fstab:
/dev/sda6 /data ext3 defaults 0 0
Since newly installing Ubuntu Karmic, it has occasionally failed to mount the disk and I get a response such as:
# mkdir /misc
# mount /dev/sda6 /misc
mount: /dev/sda6 already mounted or /misc busy
# umount /dev/sda6
umount: /dev/sda6 not mounted
(no, I don't cd to /misc). fdisk -l shows the partition
/dev/sda6 8182 38913 246854758+ 83 Linux
e2fsck /dev/sda6 returns with no errors. There is nothing obvious in /var/log/messages or dmesg, except that it notes the existence of sda6 but simply doesn't mount it.
I'm not using any sort of logical volume management, which I believe has given similar problems to this.
The kernel is 2.6.31-17-generic i686, but it happens on a couple of immediately preceding kernels. The disk drive was purchased a couple of months ago, but I am aware that there is the possibility it could still be failing early.
Does anyone have any experience or clues about what may be happening?
PS I can't tell when it will recur so I may not necessarily reply for a few days.