Differential backup with archive attribute deletion

Questions about Cobian Reflector
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lagemma2
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Joined: 15 Jan 2025, 18:11

Differential backup with archive attribute deletion

Post by lagemma2 »

I realize that it is a stretch and a contradiction to create a differential backup that deletes the archive attribute of the copied files but I have a special need that could be solved with this.
My need is to have the latest versions of some files.
After some trials with Cobian Reflector I found the solution through a differential backup where I set to keep the last 5 differential copies.
The problem is that each time I run the task it creates a copy of the file even though it has not changed from the previous copy simply because the engine does not clear the archive attribute (as is logical for a differential).
Maybe I am wrong but I think it would be enough to manage the "clear attribute archive" flag in the advanced tab for differential backups as well.
By default you can leave this flag off for differential backups and on for incremental ones but leaving the final choice to the user who can change it.
The engine then behaves based on the setting of the "clear attribute archive" flag and not based on whether it is a differential or incremental backup. I understand that it is less clean as a behavior but certainly more flexible. And it would solve a problem of mine :-D :lol:
What are your thoughts on this?
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cobian
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Re: Differential backup with archive attribute deletion

Post by cobian »

That's exactly the thing with a differential backup: it must be redundant. An incremental backup is not redundant and won't copy the files that are already copied.
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Luis Cobian
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lagemma2
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Joined: 15 Jan 2025, 18:11

Re: Differential backup with archive attribute deletion

Post by lagemma2 »

In fact, I have been using incremental backup until now. Incremental requires the periodic creation of full backups, even if there have been no changes, in order to delete old incremental copies. The differential, implemented with archive attribute logic, could continue to create copies only of changed files and delete old ones, if it allowed the archive attribute to be cleaned. This would work about the same as file versioning. As I understand it, all the flags and logic is already present and functioning in Cobian Reflector. The only thing would be to do what the "clean archive attribute" flag says for the differential as well. Please correct me if I am wrong
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cobian
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Re: Differential backup with archive attribute deletion

Post by cobian »

There is no way to fins out which files have been copied since the last full backup if the archive attribute is cleared.
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Luis Cobian
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lagemma2
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Joined: 15 Jan 2025, 18:11

Re: Differential backup with archive attribute deletion

Post by lagemma2 »

In fact, by cleaning the archive attribute, you do not get a differential backup, but a copy of only the modified files. This is a forcing, but it can have utility. I don't see why to prevent it?
Full and incremental backup considers the "clean archive attribute" property. if the flag is removed, you will no longer get an incemental backup but always a full backup. Again, this is a forcing granted to the user.
thank you for your time.
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