Thread: Burn to DVD?
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Old 06-20-2004, 10:44 AM
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Quote:
Originally Posted by sjk
Somewhere, anywhere, nowhere ...? Thanks for the ultra-quick response, which I've read you have a reputation for.
Hard to keep up my end when you reply at 2:45am my time!

Quote:
Originally Posted by sjk
Hope you can clarify a few details with this simple procedure:

1) Use "Backup - all files" script to create a bootable clone of the system volume to a backup volume.

* Since it's a bootable clone it must do root authentication but there's no mention of that in the manual.
Yes, in the current version it will prompt for authentication when you select "Start copying".

Quote:
Originally Posted by sjk
* What's the advantage of using SuperDuper for this vs. the Restore capability of Disk Copy (on 10.3)?
Selectivity, scripts, support, UI, and other features like Smart Update, Copy Different, Copy Newer, etc.

Quote:
Originally Posted by sjk
* Are any cache files removed, similar to Carbon Copy Cloner?
You can check out the scripts to see exactly what we do. The cache files are not removed, they're not copied, and are specified in the script. We don't copy things that Apple specifically states shouldn't be copied. (Obviously, it's a bit silly to copy swap files.

Quote:
Originally Posted by sjk
* Are Finder comment fields preserved?
They should be: we clone all Finder attributes and HFS+ metadata.

Quote:
Originally Posted by sjk
2) Use "Smart Update" option later to refresh copy of the system volume on a backup volume.

* I presume that's similar to using psync with Carbon Copy Cloner (which I've never done; I'm a bit suspicious of its integrity "under duress")?
Yes, it's similar, though significantly faster. I use it all the time, and have never had any kind of problem -- it's quite well tested. No doubt by consciously trying to trick it you could, but in normal (or even abnormal) operation it should be fine.

Quote:
Originally Posted by sjk
* Can any any combination of directory hierarchies be candidates for Smart Update?
Yes. I've changed a full Jaguar into a Panther with Smart Update, for example. Note that, however, we don't do an erase pass before doing a copy pass. This means that there are cases where renaming extremely large directories may end up overflowing the disk because the total of the two directories is larger than the size of the drive. Again, rare... and the speed was worth it. We've only had one report of this in the field.

Quote:
Originally Posted by sjk
And all backups are started manually; no automated scheduling (yet)?
Correct. Yet.

Quote:
Originally Posted by sjk
I'd noticed support for union mounts in the man pages but hadn't considered using them in this context -- cool idea. I played with union mounts a bit to overlay local filesystems over a NFS-mounted /usr/local hierarchies on pre-Solaris versions of SunOS so I'm familiar with the concept. I'd be interested in what you discover and I might do a bit of tinkering, too. I've been trying to get more familiar with creating disk images, ensuring that owners, groups, permissions, etc. are accurately preserved.
I've got to find the time for exploring, but I thought it was an intriguing concept, too.

Quote:
Originally Posted by sjk
Seems that incremental (and differential) backups on OS X are intended more for heavy-duty (and pricier) utilities like Retrospect and BRU.
I think so, yes. But there may be others -- I honestly haven't done a survey of the various solutions. There are quite a few.

Quote:
Originally Posted by sjk
I don't see the correlation. Normally when using dump for backups the destination would be a single archive file whereas an rsync(x) destination would be a directory hierarchy. A dump|restore pipeline to another filesystem would be more like rsync(x), and cloning.
I thought I read somewhere that rsync would also output differential information that you could use. Yes, it's not dump (obviously it's not filesystem structures), but you might be able to cobble together a solution with it and some bailing wire and string!

Quote:
Originally Posted by sjk
Thanks again for the feedback and ideas.
You're welcome. Thanks for your questions and interest.
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