Backup question: Archive Attribute when doing a mirror copy

[admsupport]

Def: The purpose of the Archive attribute was clearly to quickly determine whether a file requires a back up (archiving).

When I use F5 copy folder A to B, knowing that I will not touch the files in B (mirror copy) and only modify and add new files in A and copy them over and over in B.

Does it make sens to clear the Archive attribute for source file or not?

[fgagnon]

The conditions for which you clear the Archive bit should be part the protocol you define for your backups.

For myself, I would not clear the bit when doing routine file re-arranging, or making working copies to portable media; but I would clear it when I take an official backup.  --- at least I used to do that before I started using disk shadowing, taking an incremental image 2x/day, and full image weekly.

[admsupport]

at least I used to do that before I started using disk shadowing, taking an incremental image 2x/day, and full image weekly.

Isn't it a feature of Vista? I am on XP. I read on one of your post you did not like vista (MS has two team A/B A produces good OS, B produces Bad OS, I am waiting for Windows 7 Sp1)? I found your view interesting.

I would clear it when I take an official backup

So that the files you change will be updated right.

I in the case above let's say a file "sample.txt" copied from folder A -> B
If I "clear archive attribute on source file" (so the B copy will be cleared), there will be no consequence on A (I mean every times I update "sample.txt" on A and copy it to B, the latest update will be dully copied, and the copy on B will be overwritten?)

[nikos]

to put it simply the usefuleness of A attribute is questionable. You can do the same logic using "overwrite if newer else skip" copy option, which uses file dates to check which were modified since the last "backup". There's an old blog post about this

[Cosmo]

AFAIK there is no option in x2 to respect the A attribute for copying, x2 can only remove this attribute. So without using another software for backups it does not make sense (except you want to use this attribute for a filter, but in this case you will probably the shift-f12 attempt for setting / unsetting the attribute).

As Fred said, the attribute gets relevant with backup-software; I see 2 points for that:

1) Backing up a source to a target can be done in 3 ways:
a) simply copy all; obviously this will take very much time and place, so mostly unusable.
b) compare every file by it's time stamp and copy only newer files and those not existing in the target
c) use the archive attribute (will lead mostly to the same result as b).

The difference between b and c is the fact, that with b the heads of the hard disk have to move for each and every file between the positions for the source and the target, this is time-consuming, may stress the hardware and additionally the comparison of the time attribute has to be made. With c the heads can stay at the source's position, obviously quicker. As long as you have to backup only a rather small amount of files, you will not notice a difference, but with a great number of files you will see the difference in time, especially if only a small number of files have actually to be copied.

2) Some backup software can automatically create a new folder on the target, e. g. for every day. This is useful, if you want to have a copy of a database (for example) with the state of every day, so that you can go back wherever you want (not only the last backing up state). In this case a comparison between the time-stamps would not work to decide, if a new backup is necessary. The A attribute is the only solution for that.

[admsupport]

@Nikos & Cosmos, and fgagnon

Thank you both for your explanations (especially for Cosmos' long post). It is clear now.