On Tue, 30 Nov 2010 10:32:47 -0800 Alan Evans wrote: If the cron job is running as root, you should be able to just do something like: if mount LABEL=BACKUP /backup then ...do backup stuff... umount /backup fi or you could use UUID=gibberish syntax, etc (whatever seems convenient to properly identify the partition on the usb drive).

On Tue, 30 Nov 2010 11:38:13 -0800 Alan Evans wrote: Not sure about multiple mount points. You'd think if the kernel allows it, that it would get it right, but you never know. I "hide" my backup disk so annoying automount stuff will never mount it: http://home.comcast.net/~tomhorsley/wisdom/braindump/hide-disk.html

On Tue, 2010-11-30 at 10:32 -0800, Alan Evans wrote: Alan I had a similar situation about fifteen years ago, although it was with a zip drive then. Refining my solution every time the dust hit the fan, I have arrived at the following: I made a subdirectory (/media/flash) to mount the flash drive on. I put the following entry in /etc/fstab so only the right USB drive would be mounted, and it wouldn't be mounted automagically: UUID=3470cd52-98ec-4eb8-972f-53be4909a856 /media/flash auto noauto,defaults 1 2 You can get the UUID by using ls -l /dev/disk/by-uuid The attached script (in /etc/cron.daily) runs every night. It backs up my /home stuff using dump(1), then copies some goodies to my /root/conf.d directory (where I keep stuff I need to reference when the disk crashes) and backs that up (with tar(1)). (It backs up Monday's stuff at 0330 Tuesday, etc., hence the counterintuitive file names.) By keeping the USB drive unmounted it's preserved from most disasters. By keeping it plugged in it's available for backup. By using the UUID in /etc/fstab I prevent my files from being backed up on the wrong USB drive - you know, the one you inserted and forgot to remove... If the USB drive can't be mounted, the error is in the email and the drive isn't unmounted. If there's an error during the backup, the drive stays mounted. If the drive is already mounted, it's because there was an error, so the script terminates. Root email is your friend. Don't be afraid of scripts. You learn by doing. The goal is to err, and err, and err again, but less, and less, and less.