scsi cdrom -- can't use it

[kalmia11]

I just installed RedHat 7.2 on an old computer: AST Premmia GX P133, 48 mg mem, external scsi cd rom [nec multispin 6x] ... the cd worked fine when I did the install, now I get an error:

Could not mount device ...
mount: /dev/cdrom: unknown device.

I tried using all the different names for the scsi cd that I could find [sda sda1 sdb sr0 sda4 sda0 sda2 sda3], using the command

mount -t iso9660 /dev/[device name from above] /mnt/cdrom

I have attached part of /usr/var/messages and the error messages I received from the different attempts at mounting.

:confused:

[dmsantam]

do you have scsi support compiled into your kernel? im not sure if redhat does have it standard.... maybe you could try to recompile the kernel.

[kalmia11]

I'm not sure how to check to see if scsi support is included ... I was planning to recompile the kernel anyway because of other hardware problems I have (this is an OLD system).

But that's exactly what it looks like it's doing to me ... because in /usr/var/messages, the cdrom shows up [nec, model number and everything] but then Linux acts like it isn't there because it doesn't show up in dmesgs.

My attachment didn't work last time, I am going to try it again.

Thanks for your answer!

[Radar]

For one thing you're trying to mount your /mnt/cdrom on the file system located on the first scsi hard drive /dev/sda, where the scsi cdrom is /dev/scd0.

The other thing - it looks as if the scsi cdrom module is failing to load. Maybe not the proper module to use.

[dmsantam]

it looks like the scsi module is not installed, or not installed correctly. If you are using scsi devices all the time, it's a good idea to compile support for scsi within the kernel rather than as a module.

to recompile kernel....

1. extract the new kernel, and cd /usr/src/linux-2.x.x (directory extracted to)

2. make mrproper

3. emacs Makefile

4. change EXTRAVERSION variable to your liking - as long as it is different to default

5. make xconfig

6. load configuration file if present and applicable

7. configure kernel as required

8. save configuration file

9. make dep

10. make clean

11. make bzImage

12. make modules

13. make modules_install

14. make install

15. check /etc/lilo.conf to ensure it is acceptable

16. run /sbin/lilo to write to MBR

17. REBOOT, and check for any error messages. Check /var/log/boot.log for more details

[banzaikai]

Howdy.

Yes, Redhat supports SCSI (which is why I'm using it over Mandrake). It found and configured my Adaptec aic-7xxx just fine. Looking up your computer, we find:

SCSI Chip Mfg: NCR
SCSI Chip Model: 53C810
num of SCSI channels: 1
SCSI IRQ: 11
SCSI IO start: NA

This is a standard chip. Make sure your driver shows this particular chipset (couldn't read your attachment for some reason). You may also want to check for proper IRQ and SCSI ID.

Hope this helps...

banzai

[kalmia11]

That helps enormously. I probably won't be able to do it today, (have a project I need to get out the door by Monday). But hopefully tomorrow or Monday ...

[kalmia11]

How do I compile the kernel when I can't get to the CDROM [ID 0]? The funny thing is that I have a SCSI zip drive [ID 5] which DOES load. It is daisy-chained off the CDROM (and the terminating device). I can r/w to the zip. The SCSI board is ID 4. I thought about putting the files from RedHat/RPMS on the zip drive but it's 637 MB of stuff. I don't have enough room to copy the files on the 2 GB hard drive, even though I loaded what I thought was the minimum stuff for Linux, I have about 600 MBs of space left.

Can't access the CDROM from Linux when I take the zip drive off and set termination to on on the CD.

The CDROM loads ok when I boot to DOS (I have a small DOS partition, 100 MB). I can read from it then.

I don't understand why I can load Linux from the CDROM and I can r/w from the zip but I can't read the CDROM after Linux is running.

Radar (thanks!), I have tried mounting the CD as /dev/scd0 (both with and without the zip drive), didn't work. The error message is "unknown device." The zip drive is /dev/scb4.

Thanks for all your help!

[kalmia11]

I was doublechecking 7.2 FAQs (I figured it how to compile the kernel w/o the CD--download the tar file to the zip drive and then unpack it) to see if there was anything else I needed to know, and VOILA! There's a message about CDROM fails to install after 7.2 install. AND a fix!

Duh! I should have checked there before.

So did the fix, am still going to compile the kernel, hopefully that will take care of some of my other problems (ie: the network card and the sound card).

Thanks for all your help...