Normally Time Machine is not location sensitive, for example, if you wish to use a specific backup drive at work, and a different one at home, you need to use the Time Machine Control Panel to switch between drives.

I back up my Macbook Pro using Time Machine to OS X server at both work and home.  Two different backups.  The more the better, right?  The only thing I didn’t like was having to switch the TM destination manually by going into System Preferences, Time Machine, etc.  Lots of clicks.  ”I need automagic”, I thought.  After a lot of Googling, I came up with a way that works.  Here’s how.

This blog entry explains how to switch between drives automatically using shell scripts, and Marco Polo