3 ms·

Anecdotal evidence, but I've recently gone through my ancient CD collection (in so doing, I found Ubuntu 6.04 installers, AOL dial-up CDs and other relics) and

Anecdotal evidence, but I've recently gone through my ancient CD collection (in so doing, I found Ubuntu 6.04 installers, AOL dial-up CDs and other relics) and archived them with GNU DDrescue. It had no problem reading all bar a handful of CDs from the mid-to-late 90s and early 00's - the failure rate was much lower than I expected. The failures were mostly completely visually identifiable too - the layers had started to separate. I've also been backing up personal photos to DVD annually for quite a few years. Each disc contains encrypted Duplicity files, and a PAR2 archive to assist with any deep failures of the on-medium parity. I also usually include a disk or two of pure parity archives, to handle a total failure of any disk or two in the middle. Each year I check the price of DVD vs. Blu-ray and when factoring in the cost of the burner DVD seems to stay just on top for $/GB. It doesn't help that I've still got spare DVDs lying around, and people basically give away the blanks these days. This is not my only backup strategy, but it is the only one that is cold, read-only, and offline.

mehrdadn 7y ago
> Each year I check the price of DVD vs. Blu-ray and when factoring in the cost of the burner DVD seems to stay just on top for $/GB. It doesn't help that I've still got spare DVDs lying around, and people basically give away the blanks these days. Cost is one thing, but does the capacity not bother you too? DVDs are so small in comparison to BDs. Not to mention the time you have to waste switching discs (or reading/writing them, if relevant).
- dvd-guy 7y ago
  Burning tens of DVDs is a little tiresome, but it is well enough scripted that it is easy to slowly swap them in and out while focusing on another task - the brief interruption is barely noticed. It also means that the failure of a whole disk has a lesser impact on the whole. Edit: that said, I do have a spindle of 100 CD-R that were given to me. I haven't had the motivation to use them up yet.
KozmoNau7 7y ago
I have a CD-R of "alternatively obtained software" from December 1995, which I keep around mostly out of curiosity. It's got some forgettable old games and MIDI sequencing software on it, nothing interesting at all. But I'm wondering when it'll actually start deteriorating and ultimately fail. So far it seems to still be OK.
- unimpressive 7y ago
  I would honestly just copy it as an iso with something like dd.
  - KozmoNau7 7y ago
    There's nothing of any particular value on it. I'm keeping it around as an experiment, to see how long it'll last before the data is unreadable.
masklinn 7y ago
> It had no problem reading all bar a handful of CDs from the mid-to-late 90s and early 00's - the failure rate was much lower than I expected.The failures were mostly completely visually identifiable too - the layers had started to separate. It was mostly cheap CD-R from that period, and frankly you needn't wait 20 years for them to fall apart, they'd start failing under 5. Quality CD-R from good brands survived just fine.
rolal 7y ago
There is also https://en.wikipedia.org/wiki/Dvdisaster https://en.wikipedia.org/wiki/Dvdisaster which can automatically create par2 parity when you write DVDs or Bluray. The other important thing to do is always write and verify, a lot of disc errors are there from day 1 and not from the passage of time.
calyth2018 7y ago
CDs? or CD-Rs? Your Ubuntu 6.04 installer is probably burnt onto a CDR, unless you bought a pressed copy. The AOL dial-up CDs are most certainly pressed CDs, and would have a far longer life. I've seen bit rot in as little as 5 years on cheap CD-Rs.
- dvd-guy 7y ago
  It was a mix of both - the Ubuntu 6.04 was in fact one of the freely distributed pressed ones, but many were home burned CD-Rs - photos, software, data backups, etc.

mehrdadn 7y ago

> Each year I check the price of DVD vs. Blu-ray and when factoring in the cost of the burner DVD seems to stay just on top for $/GB. It doesn't help that I've still got spare DVDs lying around, and people basically give away the blanks these days. Cost is one thing, but does the capacity not bother you too? DVDs are so small in comparison to BDs. Not to mention the time you have to waste switching discs (or reading/writing them, if relevant).

dvd-guy 7y ago
Burning tens of DVDs is a little tiresome, but it is well enough scripted that it is easy to slowly swap them in and out while focusing on another task - the brief interruption is barely noticed. It also means that the failure of a whole disk has a lesser impact on the whole. Edit: that said, I do have a spindle of 100 CD-R that were given to me. I haven't had the motivation to use them up yet.

KozmoNau7 7y ago

I have a CD-R of "alternatively obtained software" from December 1995, which I keep around mostly out of curiosity. It's got some forgettable old games and MIDI sequencing software on it, nothing interesting at all. But I'm wondering when it'll actually start deteriorating and ultimately fail. So far it seems to still be OK.

unimpressive 7y ago
I would honestly just copy it as an iso with something like dd.
- KozmoNau7 7y ago
  There's nothing of any particular value on it. I'm keeping it around as an experiment, to see how long it'll last before the data is unreadable.

masklinn 7y ago

> It had no problem reading all bar a handful of CDs from the mid-to-late 90s and early 00's - the failure rate was much lower than I expected.The failures were mostly completely visually identifiable too - the layers had started to separate. It was mostly cheap CD-R from that period, and frankly you needn't wait 20 years for them to fall apart, they'd start failing under 5. Quality CD-R from good brands survived just fine.

rolal 7y ago

There is also https://en.wikipedia.org/wiki/Dvdisaster https://en.wikipedia.org/wiki/Dvdisaster which can automatically create par2 parity when you write DVDs or Bluray. The other important thing to do is always write and verify, a lot of disc errors are there from day 1 and not from the passage of time.

calyth2018 7y ago

CDs? or CD-Rs? Your Ubuntu 6.04 installer is probably burnt onto a CDR, unless you bought a pressed copy. The AOL dial-up CDs are most certainly pressed CDs, and would have a far longer life. I've seen bit rot in as little as 5 years on cheap CD-Rs.

dvd-guy 7y ago
It was a mix of both - the Ubuntu 6.04 was in fact one of the freely distributed pressed ones, but many were home burned CD-Rs - photos, software, data backups, etc.