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tortured

Duplicate vs. synchronize

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Sometimes when I run a Duplicate backup, it begins by deleting some files.

 

Is Duplicate really a synchronize process? I would expect the program to move to the target those files that are not on the target, or that are newer versions of files that are on the target drive. I would expect, for example, that it would ignore additional files that were dragged ad hoc to the target, outside the supervision of Retrospect.

 

What is being deleted?

thx

JB

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If you set "Replace corresponding files" in the destination select, then it overwrites similar files but leaves additional ones on the destination intact.

 

If you select "replace entire disk", then the operation is a clone, removing any additional files you may have already copied.

 

In either case, deletions are possible, although I'm not positive if it reports deleting files that will be subsequently overwritten.

 

A proper "synchronize" option would be nice. Use rsync instead.

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Hi,

 

In the Destination selection for your Duplicate, please click on the drop down box and select "Replace Corresponding Files".

This will keep all additional files intact on the destination drive while copying new and changed files on the source drive.

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It's not that I want a sync so much as I want to know what Retrospect is up to. To the best of my knowledge I have only used Replace Corresponding, and in the process have only once seen the Deleting Files prompt. It was very brief. Typically source and target ocntain about 100G, so if I'd accidentally used Replace Entire I would have seen a marked difference in the amount of time required to back up.

 

What do you suppose was being deleted? Does the program actually delete those files which are being replaced, rather than simply overwriting as you would do in the Finder?

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> Typically source and target ocntain about 100G, so if I'd accidentally used Replace Entire I would have seen a marked difference in the amount of time required to back up.

 

You would only see that if you had 100G of new, updated, or changed files. It's a bit misleading, but "Replace corresponding files" should come with a disclaimer that says "but only if things have changed". This option also leaves any extra files on the destination that are no longer on the source.

 

Retrospect will not delete a perfectly good file and replace it with an identical copy, although 'replace corresponding files' sure sounds like it would.

 

I don't often do 'replace entire disk' (although 'destination' or 'volume' would have been better lexicon). I believe that mode makes the destination look like the source. It will delete files on the destination that are not on the source, and then copy any missing, new, or changed files to the destination. I don't believe it will delete a file only to copy it over, if it has not changed, although 'replace *entire* disk', sure sounds like it would (emphasis mine).

 

p.s. The Finder doesn't "overwrite" files. It secretly deletes first, then writes. Just like how a 'mv' is really a 'cp' and a 'rm'

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