External Hard Drive Activity?
 

Newbie question - I have installed SD on my 20" Imac and am backing up to an external firewire 500 G Lacie drive. Everything is working great. Setup my scheduling to backup each night and have verified that I can boot from the external drive. My question is this - ever so often, while I am working on my computer on nothing to do with backing anything up, I will hear the whine of the ext HD firing up. Exactly what's it doing? Thanks in advance, Dana B.

Hard to know. Might be spotlight... frankly, could be almost anything accessing the drive. Not SD!, though.