Having installed Fedore Core 5 from scratch a couple of days ago, I am now experiencing frustrating problems with DVD ROM drive.

>>>
[root@Xen ~]# uname -a
Linux Xen 2.6.16-1.2122_FC5 #1 Sun May 21 15:01:01 EDT 2006 i686 athlon i386 GNU/Linux
>>>

There are two DVD drives in the system, DVD RW (/dev/hdc I guess) and DVD ROM (/dev/hdd).

I proceeded with installing Xine and Mplayer from freshrmps.net using yumex.
Everything still works fine at this point, both drives are authomatically mounted and their icons shown on the desktop and in Computer dialog regardless of the disc types (Data, music or dvd film).

Then suddenly without any tampering with the system, DVD ROM became "unmountable" when the data disc in inserted.

Even DVD ROM icon disappeared from the Computer dialog. Sometimes it randomly reappears but then any attempt to mount the inserted DVD ROM data disc results with the message from gnome-mount "Cannot mount volume".

DVD RW drive (and any USB flash) is still working properly and always automounted by the system, the icon appears on the desktop and the disc contents can always be accessed in /media.

Curiously enough, when I insert a music CD in that otherwise unmountable DVD ROM drive, gnome cd player can read and play all tracks.
When I insert a movie DVD disc, I am able to play it with XINE and MPlayer.
It only does not work anymore with data discs and I dont know how to go around this problem.
I would be grateful if anyone more experienced with GNU/Linux can help me to overcome the problem.

>>>

[root@Xen ~]# lshal|grep hdc

block.device = '/dev/hdc' (string)
linux.sysfs_path_device = '/sys/block/hdc' (string)
linux.sysfs_path = '/sys/block/hdc' (string)
block.device = '/dev/hdc' (string)
linux.sysfs_path_device = '/sys/block/hdc/fakevolume' (string)
linux.sysfs_path = '/sys/block/hdc/fakevolume' (string)

[root@Xen ~]# lshal|grep hdd

storage.cdrom.hddvdrw = false (bool)
storage.cdrom.hddvdr = false (bool)
storage.cdrom.hddvd = false (bool)
storage.cdrom.hddvdrw = false (bool)
storage.cdrom.hddvdr = false (bool)
storage.cdrom.hddvd = false (bool)
block.device = '/dev/hdd' (string)
linux.sysfs_path_device = '/sys/block/hdd' (string)
linux.sysfs_path = '/sys/block/hdd' (string)
block.device = '/dev/hdd' (string)
linux.sysfs_path_device = '/sys/block/hdd/fakevolume' (string)
linux.sysfs_path = '/sys/block/hdd/fakevolume' (string)

>>>

I am experiencing the same exact problem. Have you had any luck resolving this problem?

Encountered other bugs, too.

But installed Ubuntu Linux 6.06 instead and it is probably the best Linux move one can make nowdays.

Have you tried not using the xen kernel?

Did you disabled SE-LINUX and firewall?