Data Archiving

Discussion in 'Computer Science & Culture' started by Blue_UK, Jul 29, 2008.

Thread Status:
Not open for further replies.
  1. Blue_UK Drifting Mind Valued Senior Member

    Messages:
    1,449
    Several years ago I 'archived' a TV series onto DVD-Rs.

    The series was split into two disks each with twelve episodes (no points for guessing which series

    Please Register or Log in to view the hidden image!

    ). However, upon playing the episodes back I found episodes 12 and 24 were corrupted. I presume that the files were written onto the disks in the order they appeared in Nero and therefore the episodes damaged were the ones physically located near the outside of the DVD-R (more exposure to light, somehow?).

    Which methods of data retention do does the readership suggest? I would like to keep my data on a medium that will survive at least 10 years. DVD-Rs have failed me in 2-3 years, although they weren't necessarily the best quality.

    Taiyo-Yuden DVDs kept in the dark? RAID array of magnetic disks? Printout of base-64 on non-acidic paper?!
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. kmguru Staff Member

    Messages:
    11,757
    You can keep the data on magnetic disks in low moisture and cool environment for 10 years. Better to transfer the data to another in 9 years. While stamped dvd discs last longer, the DVD-R may last only a few years. The expensive discs may last longer. You could get an online subscription to store the data too.

    The DVDRs should be kept in individual jewel cases to last longer.

    Printing out in non-acidic paper is a good idea as long as there is a way to read it back. That can last 50 to 60 years....
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Dr Mabuse Percipient Thaumaturgist Registered Senior Member

    Messages:
    714
    Proper storage conditions assumed.

    Nothing beats Magneto Optical.

    Enterprise grade tape.
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Blue_UK Drifting Mind Valued Senior Member

    Messages:
    1,449
    I'll hand-scribe base-64 onto papyrus. Maybe even 'RAID 1' the scrolls.

    I think my answer may well be magnetic disk drive, copying the data every few years.
     
  8. Stryder Keeper of "good" ideas. Valued Senior Member

    Messages:
    13,105
    Sometimes it might not be down to data corruption, I found if you take a bunch of files, compress them into a compressed format like ZIP or RAR and burn them to a disc, you will apparently have data errors if you attempt to unzip/unrar direct from the disc. This is caused by the fact that the drives only use one head to read with, so the only way around it is to copy the entire ISO (This means a virtual instance of the disc, not just the zip file) to your drive and then unzip if from your hard drive.

    The same could be said for the series you copied, copy the ISO to your drive then attempt to view it. You might find it negates the errors.
     
  9. Blue_UK Drifting Mind Valued Senior Member

    Messages:
    1,449
    They're divx avi's and the CRC failed. I can only assume, since the dye is photo-sensitive, that the SNR gradually became too low and now the data is now lost. (Yes, I could take my time with DVD recovery software but cba... I'm only interested in what to do 'from now on')
     
  10. Stryder Keeper of "good" ideas. Valued Senior Member

    Messages:
    13,105
    Seriously put them on your drive, you won't even need recovery software. It's just how compressed formats are read, doesn't work to well with single head readers (At least with the older burning programs that didn't do something similar to a defrag)
     
Thread Status:
Not open for further replies.

Share This Page