5 ms·

Totally anecdotal but just a month ago I opened a box from my last moving (ended 4 years ago...) and I found a CD-RW labeled "Backup 2001", which survived 5-6 r

Totally anecdotal but just a month ago I opened a box from my last moving (ended 4 years ago...) and I found a CD-RW labeled "Backup 2001", which survived 5-6 relocations, even an international one. Well, I put it into an USB DVD player I have aaaand, it starts spinning and spinning and spinning, and nothing shows up in Nautilus. Looking at dmesg I see a few I/O errors on the device. Then, I try ddrescue [1], start extracting an image, leave it doing its work for a couple of hours and... magic! I have a perfectly mountable disk image! I got to live again some >20 years old memories, pictures of younger me with my friends. stupid things you would save as a late nerd teen with access to the Internet and a ton of emails in Outlook Express format (guilty!) that I could not open yet. I guess the format is probably not super-hard to parse (most of the content is plain text actually) but since I'm here, if you know of something already existing to convert it to mbox/maildir it would be cool! [1] https://www.gnu.org/software/ddrescue/ https://www.gnu.org/software/ddrescue/

xerox13ster 4y ago
IIRC there was an import/conversion tool in Outlook 2003/2007.
pmontra 4y ago
I recently sampled a CD-R from late 90s, mostly videos. I couldn't open a few files. Storage: inside home, temperature range from maybe 18 at night to 35 max. I'll give a try to ddrescue.
- darkwater 4y ago
  Same storage conditions here, probably never over 30C though, but I really never cared for its storage either. Give a try to ddrescue, it's pretty straightforward to use, I just ran it with defaults and it worked pretty well, but it has a ton of parameters if you want. Now I have stored the whole disk image in the cloud (BackBlaze), let see in 2043 if I can still access it!
  - grishka 4y ago
    The problem with cloud storage is that it's a needy thing. You have to pay for it in periodic payments the whole time it exists. And it's also controlled by someone else. I do really wish there to be a type of storage medium that I could record, store somewhere, and forget about. And then when I need it years later, it would still be perfectly readable. Optical discs are indeed kinda that, but their reliability is hit or miss.
    - incrudible 4y ago
      Unless you plan on digging a hole in the forest, every type of storage is going to cost some type of upkeep.
      - grishka 4y ago
        But keeping a box of storage media in your closet doesn't cost you anything extra, as opposed to cloud storage.
        jefftk 4y ago
        How expensive is your housing per square foot? I suspect cloud storage is cheaper.
        grishka 4y ago
        I don't know how common it is to own your living space in the US, but where I'm from, it is fairly common. And I don't think "how expensive per square foot" is applicable when you aren't renting. But either way, you won't be paying more in rent and/or utilities for having an extra box in your closet.
        bluGill 4y ago
        Unless that one box is the one that causing you to buy/rent more space to store things. In general storage space is very lumpy - people have a fair amount free until they don't and need to get more space - when you get more space you tend to get a lot more. (Of course downsize/decluttering is also an option)
- Lutzb 4y ago
  You can also try readcd/readom. It's really helpful in reading badly damaged CD/CDRs.
- xattt 4y ago
  One thing that’s missing is discussion of specific disc drives. Even in the early 2000s, some were known to be picky and some were flawless. It could be a case of using the original drive to read the media, versus some cost-cut version that’s on the market these days.
mpol 4y ago
Even with ddrescue you might lose a few bits. You will only find out when accessing those specific files and bits. For my photo history I prefer to keep PAR files next to it. On a running mechanical disc I haven't seen issues when running the repair. I do expect to see some errors in the future and as long as it stays under a certain percentage, things will be fixable. I started doing this long time in the past, when harddisks were awful. I would often lose mp3 files due to damage. With mp3 you can easily hear it. With jpeg images you can often see damage as well.
- mrjin 4y ago
  Not much point, way too time consuming. I dumped hundreds of CDs/DVDs as most of them were unreadable. 20% of them might still good, but really no longer had that energy to savage them.
- necheffa 4y ago
  If you pay attention to the ddrescue output it is pretty obvious when you are missing a few bytes here and there. I have long since moved away from optical media, really for anything, but especially archival. Long term storage to me looks like an array of magnetic disks held together with ZFS.
- acomjean 4y ago
  Could you explain the PAR file and why that would help?
  - loeg 4y ago
    PAR files are a form of Forward Error Correction (FEC) (implemented with Reed Solomon). They can be used to repair some percentage of damaged blocks in a file or set of files. The percentage is determined ahead of time when you generate the FEC (PAR files) and imposes the same amount of storage overhead (i.e., 15% redundancy costs 15% additional disk space with Reed-Solomon). https://en.wikipedia.org/wiki/Error_correction_code#Forward_error_correction https://en.wikipedia.org/wiki/Error_correction_code#Forward_... https://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correction https://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_cor...
gorbachev 4y ago
I recently got rid of all my CD-Rs I'd use for archiving back in the day. Moved everything to a NAS and dumped CDs. The earliest CDs I had were from 1994 or so, though most were from early 2000s. They were mostly cheapest CD-Rs you could buy back then, so I was expecting most of them be completely unusable. But most of them still read perfectly. I had maybe half a dozen (out of hundreds) that were completely unreadable, mostly due to peeling, about a dozen that were functionally unreadable, because there were so many unreadable files I couldn't save anything complete out of them, and maybe 10% that had less than 10 unreadable files on them. I was surprised. I was really expecting almost all the early ones to be dead.
- cronix 4y ago
  My earliest ones still read. My later ones mostly don't. I'm guessing the difference is the earlier ones were recorded at 2x speed (fastest that existed) while the later ones were recorded much faster (probably 8x or 12x), which means less laser burn in time? Really not sure. Either that or the yamaha drive was just much better than the later model plextor.
  - b112 4y ago
    Yamaha... anyone that makes both snowmobiles and guitars, is cool enough to make my cd writer. (And bizarrely, they did seem to make excellent ones)
iicc 4y ago
>Outlook Express format http://fileformats.archiveteam.org/wiki/Outlook_Express_Database http://fileformats.archiveteam.org/wiki/Outlook_Express_Data...
- darkwater 4y ago
  Nice link, thanks! With my searches I wasn't able to find it but this [1] looks promising. Let see how bit rot affects a 8 years old Linux release... [1] https://sourceforge.net/projects/ol2mbox/ https://sourceforge.net/projects/ol2mbox/ EDIT: mmh looks like it's now `libpst` and it's actually in the Debian/Ubuntu repos...
polygloty 4y ago
Isn't archiving on a HDD a more robust solution?
- vel0city 4y ago
  Depends on the quality of the archival media. Magnetic hard disks aren't without their own failure modes. The magnetic signals on the disk eventually fade causing errors. Motors and arms fail. Cosmic rays flip magnetic state. Or just stray strong magnets if you don't store it right. Really good archival optical media isn't susceptible to the same cosmic ray it magnetic fade while reducing the chances of disc rot or delamination.
  - kragen 4y ago
    Stray strong magnets haven't been a problem for magnetic hard disks for 30 years. I don't think the fading of the magnetic domains on the disk is a problem over merely geological time scales either, though I'd be interested in finding out if I'm wrong. The mechanical parts are the big deal, and for recent disks (last 25 years) there are also concerns with onboard Flash or other EEPROM losing state. Cosmic rays will eventually destroy anything that doesn't have an active repair process, including archival optical media, but the time scales are longer than when the Sun is predicted to swallow the Earth. See also my comment yesterday: https://news.ycombinator.com/item?id=33116760 https://news.ycombinator.com/item?id=33116760
ja27 4y ago
I've oddly noticed zero issues reading CD-R's going back to 1999 as recently as last year. I could certainly have some unnoticed bitrot but compressed archives have restored fine.
dehrmann 4y ago
What's crazy impressive is this was a CD-RW, not a CD-R.
grouseway 4y ago
Outlook may have used Windows structured storage back then -- but then again it could just be my imagination. https://learn.microsoft.com/en-us/windows/win32/stg/structured-storage-start-page https://learn.microsoft.com/en-us/windows/win32/stg/structur... e.g. https://www.mitec.cz/ssv.html https://www.mitec.cz/ssv.html
shostack 4y ago
Is there a good Windows option for DVD-R and RW recovery?

xerox13ster 4y ago

IIRC there was an import/conversion tool in Outlook 2003/2007.

pmontra 4y ago

I recently sampled a CD-R from late 90s, mostly videos. I couldn't open a few files. Storage: inside home, temperature range from maybe 18 at night to 35 max. I'll give a try to ddrescue.

darkwater 4y ago
Same storage conditions here, probably never over 30C though, but I really never cared for its storage either. Give a try to ddrescue, it's pretty straightforward to use, I just ran it with defaults and it worked pretty well, but it has a ton of parameters if you want. Now I have stored the whole disk image in the cloud (BackBlaze), let see in 2043 if I can still access it!
- grishka 4y ago
  The problem with cloud storage is that it's a needy thing. You have to pay for it in periodic payments the whole time it exists. And it's also controlled by someone else. I do really wish there to be a type of storage medium that I could record, store somewhere, and forget about. And then when I need it years later, it would still be perfectly readable. Optical discs are indeed kinda that, but their reliability is hit or miss.
  - incrudible 4y ago
    Unless you plan on digging a hole in the forest, every type of storage is going to cost some type of upkeep.
    - grishka 4y ago
      But keeping a box of storage media in your closet doesn't cost you anything extra, as opposed to cloud storage.
      - jefftk 4y ago
        How expensive is your housing per square foot? I suspect cloud storage is cheaper.
        grishka 4y ago
        I don't know how common it is to own your living space in the US, but where I'm from, it is fairly common. And I don't think "how expensive per square foot" is applicable when you aren't renting. But either way, you won't be paying more in rent and/or utilities for having an extra box in your closet.
        bluGill 4y ago
        Unless that one box is the one that causing you to buy/rent more space to store things. In general storage space is very lumpy - people have a fair amount free until they don't and need to get more space - when you get more space you tend to get a lot more. (Of course downsize/decluttering is also an option)
Lutzb 4y ago
You can also try readcd/readom. It's really helpful in reading badly damaged CD/CDRs.
xattt 4y ago
One thing that’s missing is discussion of specific disc drives. Even in the early 2000s, some were known to be picky and some were flawless. It could be a case of using the original drive to read the media, versus some cost-cut version that’s on the market these days.

mpol 4y ago

Even with ddrescue you might lose a few bits. You will only find out when accessing those specific files and bits. For my photo history I prefer to keep PAR files next to it. On a running mechanical disc I haven't seen issues when running the repair. I do expect to see some errors in the future and as long as it stays under a certain percentage, things will be fixable. I started doing this long time in the past, when harddisks were awful. I would often lose mp3 files due to damage. With mp3 you can easily hear it. With jpeg images you can often see damage as well.

mrjin 4y ago
Not much point, way too time consuming. I dumped hundreds of CDs/DVDs as most of them were unreadable. 20% of them might still good, but really no longer had that energy to savage them.
necheffa 4y ago
If you pay attention to the ddrescue output it is pretty obvious when you are missing a few bytes here and there. I have long since moved away from optical media, really for anything, but especially archival. Long term storage to me looks like an array of magnetic disks held together with ZFS.
acomjean 4y ago
Could you explain the PAR file and why that would help?
- loeg 4y ago
  PAR files are a form of Forward Error Correction (FEC) (implemented with Reed Solomon). They can be used to repair some percentage of damaged blocks in a file or set of files. The percentage is determined ahead of time when you generate the FEC (PAR files) and imposes the same amount of storage overhead (i.e., 15% redundancy costs 15% additional disk space with Reed-Solomon). https://en.wikipedia.org/wiki/Error_correction_code#Forward_error_correction https://en.wikipedia.org/wiki/Error_correction_code#Forward_... https://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correction https://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_cor...

gorbachev 4y ago

I recently got rid of all my CD-Rs I'd use for archiving back in the day. Moved everything to a NAS and dumped CDs. The earliest CDs I had were from 1994 or so, though most were from early 2000s. They were mostly cheapest CD-Rs you could buy back then, so I was expecting most of them be completely unusable. But most of them still read perfectly. I had maybe half a dozen (out of hundreds) that were completely unreadable, mostly due to peeling, about a dozen that were functionally unreadable, because there were so many unreadable files I couldn't save anything complete out of them, and maybe 10% that had less than 10 unreadable files on them. I was surprised. I was really expecting almost all the early ones to be dead.

cronix 4y ago
My earliest ones still read. My later ones mostly don't. I'm guessing the difference is the earlier ones were recorded at 2x speed (fastest that existed) while the later ones were recorded much faster (probably 8x or 12x), which means less laser burn in time? Really not sure. Either that or the yamaha drive was just much better than the later model plextor.
- b112 4y ago
  Yamaha... anyone that makes both snowmobiles and guitars, is cool enough to make my cd writer. (And bizarrely, they did seem to make excellent ones)

iicc 4y ago

>Outlook Express format http://fileformats.archiveteam.org/wiki/Outlook_Express_Database http://fileformats.archiveteam.org/wiki/Outlook_Express_Data...

darkwater 4y ago
Nice link, thanks! With my searches I wasn't able to find it but this [1] looks promising. Let see how bit rot affects a 8 years old Linux release... [1] https://sourceforge.net/projects/ol2mbox/ https://sourceforge.net/projects/ol2mbox/ EDIT: mmh looks like it's now `libpst` and it's actually in the Debian/Ubuntu repos...

polygloty 4y ago

Isn't archiving on a HDD a more robust solution?

vel0city 4y ago
Depends on the quality of the archival media. Magnetic hard disks aren't without their own failure modes. The magnetic signals on the disk eventually fade causing errors. Motors and arms fail. Cosmic rays flip magnetic state. Or just stray strong magnets if you don't store it right. Really good archival optical media isn't susceptible to the same cosmic ray it magnetic fade while reducing the chances of disc rot or delamination.
- kragen 4y ago
  Stray strong magnets haven't been a problem for magnetic hard disks for 30 years. I don't think the fading of the magnetic domains on the disk is a problem over merely geological time scales either, though I'd be interested in finding out if I'm wrong. The mechanical parts are the big deal, and for recent disks (last 25 years) there are also concerns with onboard Flash or other EEPROM losing state. Cosmic rays will eventually destroy anything that doesn't have an active repair process, including archival optical media, but the time scales are longer than when the Sun is predicted to swallow the Earth. See also my comment yesterday: https://news.ycombinator.com/item?id=33116760 https://news.ycombinator.com/item?id=33116760

ja27 4y ago

I've oddly noticed zero issues reading CD-R's going back to 1999 as recently as last year. I could certainly have some unnoticed bitrot but compressed archives have restored fine.

dehrmann 4y ago

What's crazy impressive is this was a CD-RW, not a CD-R.

grouseway 4y ago

Outlook may have used Windows structured storage back then -- but then again it could just be my imagination. https://learn.microsoft.com/en-us/windows/win32/stg/structured-storage-start-page https://learn.microsoft.com/en-us/windows/win32/stg/structur... e.g. https://www.mitec.cz/ssv.html https://www.mitec.cz/ssv.html

shostack 4y ago

Is there a good Windows option for DVD-R and RW recovery?