The other day, I received some Windows 7 recovery discs from Lenovo warranty services. While I hope to be able to use them again and again for years, they look homemade and not necessarily designed to last. I imagine that some of the discs are bootable while others are not. What are some ways of preserving the data? What I have in mind is something like this: Load the disc into a Linux box and run a checksum on the entire disc. Create an image and save it to the HDD. Run a checksum of the new image and hope it matches the disc's checksum. If the two checksums match, then I know that if I simply save the image somewhere safe, then I will always be able to burn a new copy when needed. I've never actually tried to do that and honestly I don't exactly know how. If there's something wrong with using that method, then an alternative would be to try a direct replication using two drives simultaneously. One drive would contain the original source disc; the other drive would burn to an archival DVD made of gold. Any ideas are welcome and appreciated.
Can't speak for Linux. Windows will do it. Create the ISO and verify, then do as you stated. Mount the ISO as a drive and compare them as a double check maybe? Any disks written should match the original md5 and you don't have to have a gold master.
Every single disc burning program I've run since the '90's (when burners were $5K and frequently made coasters) has a verify copy option. As far as longevity, the only concern I saw was years ago about the glue breaking down after 20 years. Finally, cheap writables are blue; the more silver in colour, the better the quality. Of course, this could mean the difference between 20 years and 200 years for all we know. I use Ashampoo; they're always giving their stuff away (prior versions but if it was good last year it is still good this year). I really can't think of a bad burning program; they all do the job.
i know from personal experience that if you leave a stack of them in (sometimes) 35c/95f heat for a summer or two they end up bound together. Most people are more sensible than that of course...
As far as longevity goes, I would'nt trust anything of value to an optical disk. 5 years after burning, and kept seperate, some of mine developed bubbles in the layer. Totally pointless for archival IMO.
For your case a simple iso image of the optical disks burned to the hard drive which can later be burned back to optical disks will be fine. However, if you want "a perfect optical disc replication" then you need to get a software like Alcohol 120% that does a 1:1 (sector-by-sector) copy of your original discs. I learned this the hard way when I was backing a game CD many years ago, and even though I had the complete iso image of my CD, the copy I burned with that iso would not install. I later learned that the installation exe was looking for certain files to be present in certain sectors of the disk. Making a 1:1 copy of the CD with Alcohol 120% worked fine.
These programs work for regular CDs, such as OS cds or data CDs. For games you have to go with either Alcohol 120% or Daemon Tools Pro. For music and/or movie CDs, you have to use Slysoft CloneCD/CloneDVD. Otherwise your disk image made from the CDs won't work properly.
Buy a LG M-Disc compatible burner, either DVD or BluRay, then burn your most important data to the M-Disc (can be either M-Disc DVD media or Bluray media). The blank media are a bit pricey but they will last hundreds of years. "M" standards for Millennial Disc, so theoretically your data will last thousands of years. https://en.wikipedia.org/wiki/M-DISC
I myself am somewhat obsessive on the longevity and reliability of the most important data, so I did a bit research. M-Disc appears to be the only way to go if you really want to archive your data for the long run. Of course, I will also save these data on several traditional HDDs, and transfer these data to new HDDs every 10 years. This way you can keep your data with you all your life long. Then at the end of your life, pack all the M-discs and the HDDs and bury them with you in your grave. LOL. a perfect ending.