Swapping Multiple Off-Site External Drives

[DebNCgal]

All the drives have existing data on them already. (I've been "backing them up" the hard way -- copy and drag -- but that was a very cumbersome and inefficient route, as you might imagine!)

I appreciate the tip on the drive names. I didn't realize a number at the end of the name could be a problem with OS X.

Thanks very much for the quick and helpful response.