Surprisingly, I'm getting good data from CD-Rs more than 14 years old, and from DVD-Rs nearly 12 years old. Your mileage may vary.A year ago I repeated the mind-numbing process of feeding 45 disks through the reader and verifying their checksums. It is time again for this annual chore, and once again this year I failed to find any errors. Below the fold, the details.
- Month: The date marked on the media in Sharpie, and verified via the on-disk metadata.
- Media: The type of media.
- Good: The number of media with this type and date for which all MD5 checksums were correctly verified.
- Bad: The number of media with this type and date for which any file failed MD5 verification.
- Vendor: the vendor name on the media
One observation is that the Mint Linux system I used to check the CDs (and a few of the DVDs) currently runs kernel version 5.0.0-32-generic. Each of the CDs read perfectly, but as each was mounted the kernel logged the following error:
kernel: [ 182.504692] sr 2:0:0:0: [sr0] tag#0 CDB: Read(10) 28 00 00 05 64 30 00 00 02 00 00 00 kernel: [ 182.504699] print_req_error: critical target error, dev sr0, sector 1413312 flags 80700 kernel: [ 183.315607] sr 2:0:0:0: [sr0] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE kernel: [ 183.315613] sr 2:0:0:0: [sr0] tag#0 Sense Key : Illegal Request [current] kernel: [ 183.315616] sr 2:0:0:0: [sr0] tag#0 Add. Sense: Invalid field in parameter list kernel: [ 183.315621] sr 2:0:0:0: [sr0] tag#0 CDB: Read(10) 28 00 00 05 64 30 00 00 02 00 00 00 kernel: [ 183.315624] print_req_error: critical target error, dev sr0, sector 1413312 flags 0 kernel: [ 183.315632] Buffer I/O error on dev sr0, logical block 176664, async page read