FWIW, Carbon Copy and Disk Utility copy (not sector copy) duplicates of volumes 
are not identical to the original. I have extensively sorted this out using du, 
diff, md5 and hfsdebug. Creation and modified dates that are not exactly reset 
from original, ACLs not restored from original. And most frequently what's not 
restored correct is File Security Information - the consequences of which I 
don't know. And then also Attributes. A huge percentage of small system help 
and programs (the small BSD programs) are not stored anymore in the data fork. 
Apple is compressing them, and putting them in the Attribute File, a component 
of HFS just like the Catalog File. So these files take up zero sectors on disk 
since they are stored in the Attribute File. When duplicated in any way other 
than a Time Machine restore or sector copy, these files are extracted from the 
Attribute File, decompressed and resaved as normal data fork files. They double 
or quadruple in size. On a recent restore this ended up making out for about 2G 
worth of difference.

I'm not entirely happy with Time Machine restores either, but so far they've 
been the fastest and the best overall. The only thing that's exact is a sector 
copy. I have not tested Super Duper. But it's also not free, Time Machine is, 
Time Machine works pretty well overall except apparently I can't get it to 
backup non startup disks.

Chris Murphy

On Mar 6, 2011, at 10:41 AM, LuKreme wrote:

> On 6-Mar-2011, at 07:28, Ashley Aitken wrote:
>> 
>> However, I have used Carbon Copy Cloner to copy the disk onto another disk 
>> without problem. I assume this means CCC is just copying what it thinks is 
>> correct and the resulting disk may be missing data, files, etc.
> 
> I think CCC is smarter than this. And yes, it can succeed when DiskCopy 
> fails. In all likelihood, the CCC copy is good.
> 
> Disk Warrior is a good too to have. It's not terribly expensive, and it will 
> save you from a lot of problems that other tools don't (of course, there are 
> also a lot of things it can't do, so it's not a total solution).
> 
> Disk Warrior's ability to rebuild the directory structure has saved me 
> several times.
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