Backing up 2 hard drives??
 

I am looking to purchase an external hard drive for data (video) storage. Can I use my designated backup drive to backup BOTH my internal HD and my new external HD?

PS... I am also running time machine to my backup drive.
I have the registered version of SuperDuper!

Yes, partitioned properly into enough volumes to handle this. For example, one for Time Machine, one for the internal drive, one for the external. You can't store two backups alongside Time Machine data without using images for both (which I don't recommend).

I want to back-up a system where I've relocated my home directory to another volume. Basically, everything is under / except my live home directory which is under /Volumes/another_volume/Users/my_home_dir .

In the /Users directory I've renamed the original, unused home dir my_home_dir.old.

I thought I could include the relocated home directory by adding a custom back-up script entry where I COPY /Volumes/another_volume/Users/my_home_dir but this has no effect whatsoever.

If omit the "/Volumes/another_name" per the guideline given in a FAQ on this forum, then again nothing happens because there is no directory named "my_home_dir" in /Users (it's in /Volumes/another_volume/Users/).

I am sure I'm missing something. Can you shed any light on this problem?

You'll want to pick "another_volume" in the source pop-up, and probably use "Backup - all files".