About dmesg

[youhaodeyi]

I use dmesg to get some information on a system. But it displays many errors:

...
sr: Current: sense key: Hardware Error
Additional sense: Id CRC or ECC error
sr0: CDROM (ioctl) error, command: <6>Test Unit Ready 00 00 00 00 00 00
sr: Current: sense key: Hardware Error
Additional sense: Id CRC or ECC error
...

I don't know why?

[BillT440]

does certain media (music cd / data cd / data dvd / movie dvd) do this? Or just one specific disc? I know that some time ago, forced CRC errors on media was used as copy protection. Otherwise, maybe your drive is on it's way out?