I have recently had to replace my startup drive on my Mac Pro as it was failing. I used SuperDuper! for this, and the clone is working fine as my new startup drive. I then went to run my next time machine backup (i backup to a time capsule), and time machine connected to the existing backup but wanted to backup everything as if backing up for the first time.

So i did a bit of researching around, and found this hint:

10.5: Reconnect Time Machine backup after drive swap - Mac OS X Hints

which changes the UUID registered with time machine, from the old drive to the new drive, so that it thinks that it's the old drive and carries on where it left off. i followed the instructions in the hint carefully and everything seemed to go right (i had to copy fsaclctl from an old leopard backup as it is missing in snow leopard). but when i ran the next backup again time machine wanted to backup everything.

towards the bottom of the hint, there is a comment about the UUID generated under snow leopard, as follows:

"I'm concerned that the output of xattr showed 37 hex pairs, not the 32 hex digits and dashes. By the looks -- I've forgotten all my ASCII -- it is a hex representation of the actual hex UUID (43 41 ...) and its dashes (2D), terminated with 00. That's arguably the same as the UUID, but not quite close enough to give me the warm & fuzzies"

So if anyone can help me get this working right, using the method described in the hint, or some other method, i would be very grateful. Seems like my scenario isn't that uncommon (changing a startup drive), and it baffles me that there isn't a more straightforward way to make this work.