

DVDisaster: Error correction for DVDs - pmoriarty
http://dvdisaster.net/en/index.html

======
shard
Does this offer any benefits over burning multiple copies of the data? With
media being as inexpensive as it is today, it seems more effective to simply
burn multiple copies and distribute them geographically as opposed to replying
on yet another software layer which needs to be maintained. I have CDs burned
from a decade ago with Parchive parity files included, but now Parchive is
pretty much abandoned. Therefore any system such as this is more akin to a
short-to medium-term integrity protection system than a long term solution.

~~~
pmoriarty
Multiple CDs/DVDs could develop errors in them by the time you try to read
data off of them, especially if you bought them from the same vendor around
the same time.

parchive files are great, but they won't help if the metadata referencing them
doesn't get corrupt. The DVDisaster site talks about this in a section called
_" Shortcoming of file based recovery on optical media"_.[1]

I personally like to secure my backups using all three methods:

    
    
      A - Create par2/QuickPAR error correction files
          of all my important data.
    
      B - Augment the ISOs that I create of my important data and the
          par2/QuickPAR error correction files I created in step A with
          error correction data using DVDisaster.
    
      C - Burn multiple DVDs from different vendors and bought at
          different times with the augmented ISOs I created in step B.
    

I also periodically make ISOs from old DVDs (created using the above method),
correct any errors they may have developed using DVDisaster and par2/QuickPAR,
and burn them on to new DVDs.

This method requires more time, money, and DVDs than using any subset of the
above, but it gives me more confidence in being able to get at my important
data when I need it.

[1] -
[http://dvdisaster.net/en/qa.html#recovery](http://dvdisaster.net/en/qa.html#recovery)

