[close04]

I think making a list of the files to be copied and their hashes, then a list of files that were copied and their hashes, then comparing the 2 lists should provide an even quicker way to validate. Or even hashing the entire source and destination (hash of the list of hashes) and providing both values to the user to visually compare.

As far as I can tell the method described in the article doesn't really validate the backups in any way, just provides some statistics that will fail in very plausible ways.

And of course, if the data is important to you and there are special circumstances that could affect the process, nothing beats an actual restore test.

[jaw]

I replied to a similar point about hashing here - https://news.ycombinator.com/item?id=23032633

You're correct that the methods I described are a far cry from actually guaranteeing that the backup has no errors. In the same way that a unit test doesn't prove code is error-free, but _can_ justify increased confidence in the code, I'm interested in techniques that can justify increased confidence in my backups. Particularly in cases where I don't have direct access to the original data, and where exhaustively checking the data manually is too time-consuming to be worth it.