Thank you for your helpful e-mail. I apologise for the delay in responding, but I wanted to test some more DVDs so I could try to answer your questions intelligently.
11 Dec 2025, 03:12 by [email protected]: > They are not overly verbose. Expect to see error messages from the > DVD drive or timeout messages from the driver layers in the output of > dmesg. > That's a shame. I was recently at the doctor's and musing how we'd all be dead if medicine ran anything like software development. Doctors can order a blood test and, on one sheet of paper, see what my organs are up to. It's too bad we can't do that with software. Instead, we seem to have logs that provide too much noise or not enough signal. But, I'll leave someone with more technical expertise to suggest how we fix software logging. > Did you wait for about 200 seconds after the reading program ended ? > That's usually the timeout for stuck SCSI commands. > That's helpful information. I'm not sure where that's documented. However, at times, my drive still seems to be "stuck" after several minutes of no activity. If I knew how to filter journald (or anything in /var/log) to get relevant information, I could pastebin it. I don't think anyone wants to read tens of thousands of lines of kernel messages or operating system logging. > eject /dev/sr0 > For me, if the drive is hard locked, it's soft locked, too. Having said that, I'll try waiting 3 minutes, as you previously pointed out, before cutting power. > What exactly do these error messages say ? > Again, I'll need some guidance to filter the logs to the relevant entries. > You can avoid the higher SCSI driver layers of Linux by letting xorriso > read the DVD. Maybe you get better error messages. In general it is > easier to abort xorriso than it is to abort a kernel read thread. > (xorriso uses libburn which uses the sg driver level of Linux.) > I'm confused, the xorriso documentation I read said that it's only for writing media, not reading damaged media. I'm obviously not trying to write to damaged media. That would be insane. As someone else suggested, I'm using ddrescue to try to extract from the damaged media. Are you recommending that I use xorriso to get the media's damaged blocks? To do what with?
