On 2016-10-04 16:30, jdd wrote:
Le 04/10/2016 à 14:39, Carlos E. R. a écrit :
I made a review of several compressors, none is good enough. Almost none have error recovery.
they should have:
http://www.7-zip.org/recover.html
at least the files out of the damaged part should be recoverable
Yes, I have to test it. If I recall correctly it was not proven reliable. One that is proven is rar, but it does not support all Linux attributes. Oh, looking at your link, it is terrible. With rar you simply tell the command to repair the archive and that's it.
Yes, that is true. Well, floppies were never meant for long-term storage, although I'm sure I still have some 5" up in the attic.
The original floppies sold in the 80's do last. Those made by the end of the 90's and later are terrible. Impossible to get one that lasts a month without an error. A box of ten has some that error out on format.
anyway, most people do not have floppy reader. or interface to make it work.
And those that have it, like me, would not think of doing a hard disk backup that way. LOL.
so, yes, when trying to make long term archives (one can't anymore speak of backup) have to think of the medium
for example, flash disks are known to have a short life (including ssd), I speak of time life, not number of cycles. Hard drives have good life expectancy but can dye unexpectedly.
once it was said than archive medium have to be updated at a bare minimum every 5 years. It's pretty easy as in this time price drop and size grow.
one can find dvd or BD said to be worth 1000 years. take appointment in 3000 to know :-))
Hah! :-)
https://www.nierle.com/en/article/32558/Verbatim_M-DISC_Blu-ray_BD-R_25_GB_-...
Ah. But we still do not have in Linux a backup program that gets close to what PCtools Backup did in the 80's. In this case, perform the backup to supported media with compression and forward recovery bits. See: https://en.wikipedia.org/wiki/Forward_error_correction The idea is that even if the DVD/BD gets scratches and broken sectors, up to a percent, *all* the files can be correctly recovered without errors. See also "par2". (https://en.wikipedia.org/wiki/Parchive). If you want it, build it yourself. -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" at Telcontar)