I recently installed Debian using a Knoppix CD and upgrading using apt-get. The computer has a CD/RW drive and a DVD drive. The CD/RW drive works, but DVD drive does not. If I type "ls -al /dev/dvd" I get "/dev/dvd -> /KNOPPIX/dev/dvd". This is obviously incorrect, and I think may be the root of the problem. My questions are:

1) How do you correctly remove the current symbolic link and replace it with the correct symbolic link?

2) How do I tell what a device is under Linux? For example, I know /dev/hda/ is my hard drive, but how do I tell what my DVD drive is? How do I know if the DVD should be /dev/sda, /dev/scd, /dev/hdb, etc.?

If it helps at all, the CD/RW is IDE master and DVD is IDE slave.

sc devices are SCSI and hd devices are IDE:
IDE0 Master = hda
IDE0 Slave = hdb
IDE1 Master = hdc
IDE1 Slave = hdd

To hcange the symlink you can use:
rm /dev/dvd
ln -s /dev/dvd /dev/hdd

This is assuming it is on the secondary channel - you may need to change that.

Thanks for the explanation. I have one more question. Under what circumstances should you use /dev/scd1 (my CD/RW is /dev/scd0) instead of /dev/hdd?

I actually got it working just 2 minutes before reading your reply using:

rm -f /dev/dvd/
ln -s /dev/scd1 /dev/dvd

I can now play DVDs on mplayer. Should I change it to /dev/hdd?

No not if it is SCSI - leave it how it is.

Thanks again for the information. The CD/RW is an IDE drive with SCSI emulation. I assume the DVD drive is the same with the way I set it up. Since it is working, I'll leave it alone. "If it's not broke, don't fix it." (I have a problem remembering that sometime)