I've been reading up on disc longevity on the net. I did know that manufactured cd's and dvd's should last roughly 100 years. Though no one knows anything for sure yet. What did surprise me was that burned cd's and dvd's do not last that long. No-one seems to know how long, but I've read as little as 2-5 years, though on one forum people were disputing this by saying it's more like 10+ years. A good make of disc lasts longer. Mine are Maxell. I think these are an ok brand. A few are Kodak, which I'm not so sure of. I've checked a few of my discs. All are ok so far, including the oldest one which is about 10 years old. Does anyone know anything concrete? I'm surprised our own homemade discs won't stay the course. It seems like my next job will be backing up the things I really want the most on a USB stick. Hopefully one day with all this advancing technology someone will invent something that will last. Or maybe the industry doesn't want us to own anything for too long.
They will last until you need them. lol. Murphy's law. You can check them now, and they'll be fine, and that time you need your receipts for a tax audit or photo's for a funeral or a home video for a memorial, then they won't work. I've had discs that seemed to be fine, then when my HD copy died of my photo died, went to read the disc, no good anymore.
I wouldn't trust discs for anything, plus spacewise, they are small compared to what we can do a drive now.
Just keep your important data on two different hard drives. If your backup drive dies, just get another and make another backup. If your system or data drive dies, then you've got your backup, get another system or data disk. The odds of both disks dying at the same time are really, really small. The odds of your optical disks being usable many years later when you need them in an emergency are, well, probably better than 50-50, but who wants to risk that? And as he said, optical disks don't hold much data. And they scratch easily.
The idea behind backup hard drives is that after the initial, full backup, you do incremental backups, either daily, weekly, or monthly. This regular use lets you know if they're good or not. Sticking the optical disks in a cupboard for a decade does not inspire confidence.
Manufactured CDs and DVDs use a completely different process than burned discs so should last longer. You can buy archival quality CDs and maybe DVDs which are supposed to have a lifespan of 100 years but who really knows if there will be any way to read them at that point (or anyone alive to care). If there are files that you need to save then multiple copies on different media would be best.
I've been checking all my burned cd's and dvd's. Most of them are nearly 10 years old and all seem perfect. One friend says he has a lot over 15 years old and all are fine. I do look after mine, out of daylight, away from heat, etc. I'm wondering if these cd-r's and dvd-r's are more hardy than they're given credit for. If looked after properly I'm wondering if they could last a lot longer than we think.