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Comment by useFAR | Hacker News Reader

7z does not offer archive recovery. This has saved my archived data couple of times, which would be gone, if I was using 7z.

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You can use an par2 file for that though. Yes, might be less convenient than having it built into the archive in some cases but on the other hand you can a) only download the .par2 file if you need it and b) use it to add error correction to files without putting them in an archive so you can access them directly and c) you can create the error correction information across multiple archives if you want.

This sounds sooo much like that "dropbox? Just use rsync" comment.

I don't think you'll get why having all in a simple to use solution is superior for several of us.

the dropbox joke is that nobody would use dropbox, which is obviously false in hindsight. but nobody is claiming that nobody uses rar, but instead that nobody should use rar. the same argument is valid of dropbox: https://en.wikipedia.org/wiki/Criticism_of_Dropbox.

I'm not familiar with compression very much, what's the difference between what 7z does versus "archive recovery"? Thanks

Winrar save extra information to the compressed file. So in case your .rar file damage, it can be recovered.

You'd need to use a tool like par2 (https://en.wikipedia.org/wiki/Parchive) on top of a 7z file to get a recovery record.

Some compression formats are actually designed for data archival and compression. Rar is one such format. One of the early use cases was data archival onto long term storage mediums such as tape. As such, it has built in parity which means you can recover partially corrupted archives. It can also do things like split the archive up over many smaller files. Again, because this sort of thing was needed for backing up to tape, floppy, etc in the late 90s/early 2ks.

> It can also do things like split the archive up over many smaller files.

Are there other archival formats on par with RAR without the licensing voodoo I see people mentioning?

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