Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

mattspace

macrumors 68040
Original poster
Jun 5, 2013
3,611
3,143
Australia
Hi,

Question about time machine if anyone knows a definitive answer - If you're backing up a source drive, and it's running out of capacity, and you want to migrate it to a new larger drive, Time Machine will treat that new larger drive as a completely new device, and do a full backup of it, meaning you'll have two copies of all the drive's contemporary content, and possibly lose a bunch of historical revisions if your TM volume is reaching full.

I know you can get around this with a bunch of tricks to clone the coded UUID of the original drive, and apply it to the new one so TM thinks the new drive IS the old one, but is there another way?

For example, if you restore a volume (to a new drive) from a TM backup, does Time Machine see that new drive as a continuation, or does it still do a complete backup of the restoration?

thanks.
 
I suggest backing up that source drive with either Carbon Copy Cloner or SuperDuper and then clone it to your new drive. Much simpler than what you're thinking of doing.

Yes, but Time Machine will still see that as a different set of files, and do a complete backup of them. What I'm trying to achieve is to migrate a source volume to a larger drive, while having Time Machine just continue incremental backups of the data.
 
Use CarbonCopyCloner instead.
Your problems will be SOLVED, as "easy as that".

CCC is FREE to download and use (fully-functional) for 30 days.
 
Yes, but Time Machine will still see that as a different set of files, and do a complete backup of them. What I'm trying to achieve is to migrate a source volume to a larger drive, while having Time Machine just continue incremental backups of the data.

Carbon Copy Cloner likewise can do incremental backups and with its "Safety Net" on you can always restore older files that you may need in case of an accidental deletion. I'm not saying that Time Machine should not be used, but I advise not counting on it as your primary backup source. I personally use both Time Machine and CCC.
 
Use CarbonCopyCloner instead.
Your problems will be SOLVED, as "easy as that".

CCC is FREE to download and use (fully-functional) for 30 days.

That's not solving my problem, unless CCC can adopt the existing TM backups and continue them. The goal, is to not generate a whole new set of backup files, or lose the several years of historical versioning I already have, by causing a purge when the TM volume runs out of space while attempting to keep double copies of the most recent files.
 
Last edited:
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.