can't unmount usb hd

[Matt Graham]

From: Robert Holtzman <holtzm at cox.net>
> I have a 360 Gb external drive. When I back up my system (that has 3 
> linux distros installed) with Clonezilla, the drive appears mounted as 7 
> separate [partitions] (/media/disk, /media/disk-1 thru /media/disk-6).

FTFY.  ("disk" != "partition", remember.)  You have an automounter of
some type running.  I *HATE* automounters, and I always turn them off,
but YMMV.  Which version of which distro are you running?  Check its
docs for how to turn off the automounter, or how to live with the
automounter if you decide you want it.

> itself is weird but isn't the main problem. The real hangup is that I 
> can't unmount any of them. If I run umount as root on them the icon 
> will disappear from the desktop but /etc/mtab and "ls /media" both show 
> them all as still mounted.

Automounter again.  The default seems to be that if a filesystem has
not been accessed for more than 60 seconds, it will be umounted.  If
you have some sort of indexing program like beagle running, it'll
of course be running over everything.  To figure out which processes
are using a file (or a filesystem), use lsof or fuser.  HTH,

-- 
Matt G / Dances With Crows
The Crow202 Blog:  http://crow202.org/wordpress/
There is no Darkness in Eternity/But only Light too dim for us to see