Preventing internal backup disk(s) from mounting at boot
 

On my Mac Pro, SuperDuper! automatically clones the boot drive to an internal disk every morning.

But I don't want the backup disk mounted when SD! is not running.

Topher Kessler on Macfixit has just published a way to do this, involving fairly simple editing of system files in Terminal:
http://reviews.cnet.com/8301-13727_7...&subj=MacFixIt

It seems to work, and SD! was able to mount the volume for a scheduled run.

[Previously I used a login AppleScript and shell scripts to do this, but it was clunky, and delayed user login]

I see someone has also written a Systems Preferences pane:
http://www.redcliffetechnology.com/c...t_Volumes.html

And TinkerTool System does it too:
http://www.bresink.com/osx/TinkerToolSys2.html

Thanks for the tips!