Re: [gentoo-user] Re: [OT] filesystems

["Jorge Peixoto de Morais Neto" <please.no.spam.here@gmail.com>]

On Mon, Dec 1, 2008 at 1:38 AM, Shawn Haggett <podge@podgeweb.com> wrote:
> On Sat, 29 Nov 2008 04:21:44 pm Jorge Peixoto de Morais Neto wrote:
>> Speaking of md5sum/shasum, do you know some tool that adds data
>> redundancy? I heard dvddistaster does this, but I guess it is limited
>> to DVDs. It would be great fo find a general data redundancy tool. In
>> the moment, with the tools I know, the best I can do is store the
>> files twice, with md5sums/shasums to decide which version is correct.
>
> Have a look at app-arch/par2cmdline ( http://parchive.sourceforge.net/ ). It
> will create parity files for an arbitrary set of data files and you can
> choose your level of redundency (from 0 = now redundency, just integrity
> checking, up to 100%). Although expect your parity files to be on the order
> of the percentage for size, i.e. 50% redundancy for some given files to take
> about 50% of their size for the parity files).
>
> The down side I find with the tool is that it doesn't currently support
> directories. This isn't so bad for creating parity files, but during
> checking/restore, the program expects all files to exist in the current
> directory, despite which sub-dirs they were originally in. You can get around
> this with a tar/rar/zip first, then calculate parities on the archive though.
>
Thank you very much. I have taken a quick look at this, and seems to
be what I look for. In a few days, when I have time, I will try it on
some files and see the results.