On Sat, 29 Nov 2008 04:21:44 pm Jorge Peixoto de Morais Neto wrote: > On Thu, Nov 27, 2008 at 10:12 AM, Daniel Troeder <[EMAIL PROTECTED]> wrote: > > Am Mittwoch, den 26.11.2008, 15:26 +0100 schrieb Florian Philipp: > > You can buy so called "archival grade" DVD-Rs that should work for 10-20 > > years in a good environment. There are hugh differences between > > products. In germany you can buy very good ones from Verbatim for around > > 2€/disk. > > This can be hard to find in my mid-sized Brazilian city. If I lived in > the mega-metropolis of São Paulo, this would be far easier. And thanks > very much for recommending Verbatim. I have heard of Taiyo Yuden, but > that would likely be far harder to find. > > 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. > By the way, it seems from my (limited) experience that even sha256sums > are IO-bound (even on my not-so-powerful Athlon XP 2600+), so it makes > sense to calculate sha256sums (as instead of md5sums) even it is > overkill. To be doubly sure, one can calculate sha256sums *and* > md5sums.
