CDROM Mount Problem
 

Hello to all. I have a problem that I hope someone can help me with. I'm a total virgin when it comes to Linux. I purchased a Teach Yourself Linux book about two weeks ago and here I am. The book is great for getting you from a to b, but it assumes everything is working fine. I've been unable to get my CD-ROM to mount. When I put a CD in the drive, it starts reading it immediately, which I assume means it's trying to mount it, but it starts scrolling error messages down the screen in text mode or just sits there in graphics mode. It takes a good 5 minutes for it to complete it's scan of the CD before it will unlock the tray. If I attempt to manually mount it either from the command line or through X window it immediately starts the scan again and the system is locked. This is only a small portion of the error message:

hdc: command error: Status=0X51 {DriveReady SeekComplete Error}
command error: error=0X50
end request: I/O error, dev 16:00 (hdc), sector 1024
UDF-fs: No partition found(1)

The sector number changes as it goes through the scan. I may have some of the spacing wrong. I was writing it down as it scrolled down the screen. Can someone tell me how to mount my CD-ROM? I'm running Red Hat 9.0 2.4.20-6 on a small P2 machine. I've found some other people on the net with exactly the same problem but no solution. Some feel it could be a problem with the kernel. Could it be something as simple as my CD-ROM not being compatible? I loaded the program from the CD just fine. Any ideas??????

What type of CD are you trying to mount? Music, CDRW, data, blank etc....

Data CD with drivers that I downloaded. But I tried others as well. Haven't tried a music CD yet.

It looks like the disc you're trying to mount is formatted UDF. You said it contains drivers you downloaded. I'm guessing you burned these in Windows with something like DirectCD, am I right?

You should be able to read a UDF disc (I know I can).

to help us help you can you post the contents of you /etc/fstab file? This file tells you system how to mount all the various filesystems on you computer. It's the first place to look if you're having mounting troubles.

You are correct. I did burn the CD. I'll get the information you requested tonight. Thanks for the quick response.

something to try, when you put in the disc, open a console and:
(I'm making some assumptions on your specific configurations but this is fairly common)

mount -t udf /dev/cdrom /mnt/cdrom
(you'll need to be root for this)

again, this command will vary slightly depending on what is in /etc/fstab.

Or, if you want go back to Direct CD and close the session, then try it again, it should mount automatically.

Here's my fstab file. I also tried a commercial CD with same results.

LABEL=/ / ext3 defaults 1 1
LABEL=/boot /boot ext3 defaults 1 2
none /dev/pts devpts gid=5,mode=620 0 0
/dev/hda1 /mnt/win vfat defaults 0 0
none /proc proc defaults 0 0
none /dev/shm tmpfs defaults 0 0
/dev/hda3 swap swap defaults 0 0
/dev/cdrom /mnt/cdrom udf,iso9660 noauto,owner,kudzu,ro 0 0
/dev/fd0 /mnt/floppy auto noauto,owner,kudzu 0 0

Hope this makes sense to someone.

when you've tried mounting the CD, are you logged in as root? Currently your fstab is set up to only allow the owner of the device (/dev/cdrom) to mount it. Most likely this is root. Unless you specifically want to limit access to your cdrom drive, you can change the fstab to allow any user on the machine to mount that device. To do this, go to the line related to the cdrom and change the word "owner" to "users" like this:

/dev/cdrom /mnt/cdrom udf,iso9660 noauto,users,kudzu,ro 0 0

Now, on your mounting problems. You said you tried a regular "commercial" CD. Was this a data CD?
Try the Linux CD that you installed from, as we know there is nothing wrong with that one. This should be a standard (not UDF) filesystem, which should mount automatically, or simply with the command
mount /mnt/cdrom.

Post any errors you get.

If all goes well, then try your UDF disc that you tried earlier.

The commercial CD I tried was the Linux CD.

And it gave you the same error you mentioned in your first post?

Try removing the udf entry from the fstab, so it reads:

/dev/cdrom /mnt/cdrom iso9660 noauto,users,kudzu,ro 0 0

then try mounting the Linux CD.
This is how I typically configure my systems, then when I want to mount a UDF disc I mount in manually like this:

mount -t udf /dev/cdrom /mnt/cdrom
(as root)

Or, you could try changing the entry to "auto" like this:

/dev/cdrom /mnt/cdrom auto noauto,users,kudzu,ro 0 0

hope that helps ;)

Thanks. I'll give it a try tonight. I'll post the results tomorrow.

I made the changes your suggested. I removed udf from fstab and changed owner to users. I then rebooted. Didn't know if I needed to but what the hell. After it came back up, I put the Linux boot CD in and the drive light came on for about 5 seconds and then went off. This was a big improvement over my previous situation. But when I tried to mount the CD in graphics mode, it would come back and say 'Not a directory'. When I tried from the console, I would get the same messages again. Not as many as before. It didn't seem to try as many sectors as before. I also got some new ones. The following section is a portion of my message log. The log was much larger, but this section contained the new errors. Even though I changed fstab to users, I still logged in as root, just in case.

Jun 29 20:26:55 localhost kernel: hdc: command error: status=0x51 { DriveReady SeekComplete Error }
Jun 29 20:26:55 localhost kernel: hdc: command error: error=0x50
Jun 29 20:26:55 localhost kernel: end_request: I/O error, dev 16:00 (hdc), sector 76
Jun 29 20:26:55 localhost kernel: FAT: bogus logical sector size 0
Jun 29 20:26:55 localhost kernel: VFS: Can't find a valid FAT filesystem on dev 16:00.
Jun 29 20:29:50 localhost kernel: hdc: command error: status=0x51 { DriveReady SeekComplete Error }
Jun 29 20:29:50 localhost kernel: hdc: command error: error=0x50
Jun 29 20:29:50 localhost kernel: end_request: I/O error, dev 16:00 (hdc), sector 116
Jun 29 20:29:50 localhost kernel: ISOFS: unable to read i-node block

Could this be a DMA problem?

I've been searching around quite a bit and have found a number of similar problems, but nothing as to the solution yet.

Still searching........

Just out of curiosity, have you tried any other distributions? If you can get hold of a Knoppix CD (or another distro if you want), I'd be curious if you would have the same problem.

Like you said in your first post, might be the kernel version you're running. That's about all I have left to go on at this point.

Thanks for your help. This is the first flavor of Linux I've tried. I'll let you know if I get it solved.