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zjr
06-19-2003, 07:49 PM
Drive: TOSHIBA DVD-ROM SD-R2312

The drive will not mount for whatever reason, scsi timeout error repeats until another error about trying to access past the drive.

/etc/fstab appears to be setup correctly with the right information and at boot Knoppix recognizes the drive a DVD/CD-RW drive.

No way to access drive, anyone have similar issues?

zjr
06-19-2003, 09:43 PM
Nevermind, brain fart...i should have been trying to mount /dev/sr0 all along.

rickenbacherus
06-19-2003, 11:32 PM
You can mount that way OR if you want to use

# mount /dev/cdrom

for example you'll need to make a symbolic link that connects /dev/cdrom to /dev/sr0 like this:

# ln -s /dev/sr0 /dev/cdrom

Then you can test the symbolic link you just made like so:

ls -al /dev/cdrom
It should show you that /dev/cdrom actually points to /dev/sr0

Presuming your /etc/fstab includes /dev/cdrom and a valid mount point then

mount /dev/cdrom

should mount the drive.

Of course you may call it /dev/dvd or whatever you like but most Linux apps will be looking for /dev/cdrom.

zjr
06-20-2003, 01:30 AM
You can mount that way OR if you want to use

# mount /dev/cdrom

for example you'll need to make a symbolic link that connects /dev/cdrom to /dev/sr0 like this:

# ln -s /dev/sr0 /dev/cdrom

Then you can test the symbolic link you just made like so:

ls -al /dev/cdrom
It should show you that /dev/cdrom actually points to /dev/sr0

Presuming your /etc/fstab includes /dev/cdrom and a valid mount point then

mount /dev/cdrom

should mount the drive.

Of course you may call it /dev/dvd or whatever you like but most Linux apps will be looking for /dev/cdrom.

Yeah i was aware of that, it appears my sys link to /dev/cdrom was wrong.

MorskNorsk
06-27-2003, 06:49 AM
Yeah i was aware of that, it appears my sys link to /dev/cdrom was wrong.
I had the same problem with the DVD/CD drive in my notebook. The /dev/cdrom symlink was pointing at /dev/sr0 (scsi device?) instead of /dev/hdc like it should have. Changing the symlinked fixed the problem, but I don't know how it got set to /dev/sr0 in the first place since the startup process recognizes it as /dev/hdc. Bug with the install?

Stephen
06-27-2003, 08:27 AM
I had the same problem with the DVD/CD drive in my notebook. The /dev/cdrom symlink was pointing at /dev/sr0 (scsi device?) instead of /dev/hdc like it should have. Changing the symlinked fixed the problem, but I don't know how it got set to /dev/sr0 in the first place since the startup process recognizes it as /dev/hdc. Bug with the install?

Knoppix uses scsi emulation for the drives so that's where the sr0 comes from and the /dev/sr0 would be linked to /dev/scd0 the first scsi device it should have worked but apparently did not perhaps you should file a bug (http://www.knoppix.net/bugs/) report.

MorskNorsk
06-27-2003, 03:15 PM
Knoppix uses scsi emulation for the drives so that's where the sr0 comes from and the /dev/sr0 would be linked to /dev/scd0 the first scsi device it should have worked but apparently did not perhaps you should file a bug (http://www.knoppix.net/bugs/) report.
So SCSI emulation would make it point to a SCSI device entry? Interesting. Never fooled around with SCSI emulation before. It seems kind of silly to use it for common devices like CD drives and the like. I'm sure there is a reason for doing so though. Care to enlighten me? I'd file the bug report but I rebuilt my kernel with 2.4.21 and I could have left something out of the kernel that may have caused the problem.

Stephen
06-27-2003, 04:20 PM
So SCSI emulation would make it point to a SCSI device entry? Interesting. Never fooled around with SCSI emulation before. It seems kind of silly to use it for common devices like CD drives and the like. I'm sure there is a reason for doing so though. Care to enlighten me? I'd file the bug report but I rebuilt my kernel with 2.4.21 and I could have left something out of the kernel that may have caused the problem.

It is used for burners they use scsi emulation to write CD's. You most likely left out the option for scsi emulation when you compiled the 2.4.21.

MorskNorsk
06-27-2003, 05:52 PM
It is used for burners they use scsi emulation to write CD's. You most likely left out the option for scsi emulation when you compiled the 2.4.21.
Don't believe so. I include it so that I can use my CF/SM flash reader. These are the modules I have built for SCSI:
jebediah@ark:/lib/modules/2.4.21/kernel/drivers/scsi$ ls
ide-scsi.o scsi_mod.o sd_mod.o sg.o sr_mod.o

Stephen
06-27-2003, 06:14 PM
Don't believe so. I include it so that I can use my CF/SM flash reader. These are the modules I have built for SCSI:
jebediah@ark:/lib/modules/2.4.21/kernel/drivers/scsi$ ls
ide-scsi.o scsi_mod.o sd_mod.o sg.o sr_mod.o
Well you have the required modules so there is something strange that happened maybe you should file a bug report even with the new kernel. Was there anything in dmesg about passing the drive to scsi emulation that should be there for it to work, also an idea did you change lilo to remove in the append line the hd?=scsi for the drive when you installed the new kernel.

MorskNorsk
06-28-2003, 05:57 AM
My dmesg from using the default kernel is gone now :( Got flushed days ago. I did switch to GRUB instead of LILO. That must be what caused the problem. Looking in my /etc/lilo.conf file showed the line
append="hda=scsi hdb=scsi hdc=scsi hdd=scsi hde=scsi hdf=scsi hdg=scsi hdh=scsi apm=power-off nomce" which I didn't transfer over to GRUB. Nice to know it isn't a bug :)

Stephen
06-28-2003, 06:31 AM
My dmesg from using the default kernel is gone now :( Got flushed days ago. I did switch to GRUB instead of LILO. That must be what caused the problem. Looking in my /etc/lilo.conf file showed the line
append="hda=scsi hdb=scsi hdc=scsi hdd=scsi hde=scsi hdf=scsi hdg=scsi hdh=scsi apm=power-off nomce" which I didn't transfer over to GRUB. Nice to know it isn't a bug :)
Good to hear you tracked it down and seeing as the drive is not a burner you don't really have to modify GRUB at all, the drive will work fine as it is.