Thread: Burn to DVD?
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Old 06-18-2004, 11:47 PM
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dnanian dnanian is offline
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I'm not even sure where to start here, I have to say!

One of the problems of 'clone' type backup utilities -- of which SuperDuper! is one -- is that it becomes awkward to try to develop a backup strategy that allows full rollback with incremental update storage. In general, doing that kind of things requires a backup catalog and a non-simple-filesystem storage mechanism, and we've been trying to avoid that.

Yet, in my quest for trying to figure out how to do this simply, I did stumble on some discussion (in the mount docs) of union mounts. It seems to be that a union mount of an image over another image might allow clone backups to be done while actually generating a storable delta in a separate image. I haven't done a full-fledged investigation into this, but it was an intriguing idea. You might want to check it out.

SuperDuper! can certainly make and update images, and you can front-end this stuff with various hdiutil functions to mount, create, or whatever, but without doing this kind of trick you won't have incremental rollback.

Of course, you could have a number of sparse images stored on an external or network drive, named things like "monday", "tuesday", etc, and Smart Update them; you could roll back as many days as you have storage for.

Another option, if you're thinking dump: rsyncx...

Anyway, just throwing some disorganized, rambling, I'm-on-a-slow-GPRS-connection-and-can't-research-much ideas out there.
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