Migrating TM backup from USB drive to ReadyNAS

Here's a running dialog of what's going on with this - I apologize for the decidedly not concise message, but it's a running log so I'm just jamming stuff in here until I'm done with this try. The subject gives you a quick hint as to the ultimate result.

• Using the source computer (the source of the backup), I followed steps 2 and 3 (I had already done step 1 and have 1 other computer already backing up to the NAS).


• Moving to a surrogate computer (one different than the source of the backup), I started the restore. Since the restore function is largely a block-level copy of one disk to another, that should not matter, but we'll see. I chose to use a surrogate because it was on the Gig-E network while the other one is connected via 802.11n and I didn't anticipate any problems because of it. I could have used the source, but my wife wanted to keep using it to play some games on Facebook or something.... Whatever happens, if it worked or not, losing sleep wouldn't have helped, so I'm off to bed. I'll check in the morning.
• The restore finished successfully. I suspect this was at about 2 AM, 6+ hours after I started the restore.


• When I mount the sparsebundle on the surrogate, it mounts successfully and looks like the original disk. So much so that the name of the volume inside the sparsebundle is the same as the name of the disk I restored to it and the top level directory structure of the backup has the same number of entries - I take it as a good sign that the entry count is the same and I wonder if that will cause any issues with TM backups that the volume name is different. (NOTE: the sparsebundle name is unchanged, which I take as a good sign).


• Moving back to the source computer, prior to turning Time Machine back on, I entered Time Machine to see what kinds of backups I actually have there - this tests 2 things: a) Does the change in volume name cause any problems? b) Did all the backups make it across? The answers are No and Yes respectively. This is a good sign.


• Pushing my luck, I turn Time Machine back on and start a backup. I'm expecting it to have to do a deep traversal but it doesn't - intriguing. The last backup on the old drive was 2-3 days ago, and I suspect that Time Machine sees the NAS-based volume as simply the same one it was using so everything is happy-happy.


• About 2 MB was backed up, and when I left for my office today it was busy finishing up that backup - in the "post-backup thinning" phase where it consolidates and deletes various versions. Since it's been a few days, there's likely to be some of that kind of work that's necessary

I'm ready to conclude that it was successful. I'll check again when I get home to make sure that backups have been going all day, or at least while the computer has been awake, but it seems like all the machinery is in place and doing the things it's expected to be doing.

I'd like to thank mgdm and sphardy for their guidance. If this procedure isn't written up as a sticky under the Time Machine sub-topic it should be.