Place a cdrom into the drive. Mount it either via "mount /mnt/cdrom" or from within Gnome and clicking on the cdrom icon. Then on the front of the drive hit the manual eject button. The disk is spit out but the os still thinks it is still mounted. You can put a different disk in and close the door. The os will see the event but still thinks the previous filesystem is mounted. Further the mount point is now busy and difficult to umount.. The drive I have in the system is a year old and supports notification of manual eject as well as lock out. I beleive it is a standard ATAPI DVD-ROM. Perhaps that is the problem. Distribution: Red Hat Linux Operating System: Linux Distribution Version: Red Hat Linux release 7.0 (Guinness) Operating System Version: #1 Tue Aug 22 16:49:06 EDT 2000 Operating System Release: 2.2.16-22 Processor Type: i686 Host Name: hunkingiron User Name: cire X Display Name: :0 System Status: 12:05am up 36 min, 2 users, load average: 0.26, 0.33, 0.27
There is a new set of sysctls controlling cdrom behavior. One of them enables door locking. It is possible that it is not set. Check the contents of /proc/sys/dev/cdrom/lock to see if it's 1, if so it lock the door. If it's 0, it doesn't lock the door. For additional debug information, echo a 1 into /proc/sys/dev/cdrom/debug and tail -f /var/log/messages while pressing the eject button. In a normal loop with device unmounted it unlocks the cdrom door each time through. If lock is set to 1 when looped through and the cdrom is mounted, it does not unlock the door, which prevents ejection via the front panel button. It's possible that the default is 0 in the redhat kernel, or a program at startup is setting lock to 0.
On further research this looks like a Gnome problem. Gnome can be configured so that cdroms are auto mounted on insertion. When this is the case you can insert a cdrom and it will be mounted. Now when you hit the manual eject button, the disk will be ejected regardless of the setting of /proc/sys/dev/cdrom/lock. The problem then becomes that Gnome doesn't unmount the cdrom filesystem. Seems that when cdrom automount is turned on the front panel button should eject the disk. Gnome seems to have a bug where it doesn't unmount correctly. This bug should probably be forwarded to the gnome team.
"the disk will be ejected regardless of the setting of /proc/sys/dev/cdrom/lock" implies a kernel bug