# The Answer Gang 65: cd-writing mini-howto

# The Answer Gang

#### By Jim Dennis, Ben Okopnik, Dan Wilder, Breen, Chris, and the Gang, the Editors of Linux Gazette... and You!
Send questions (or interesting answers) to linux-questions-only@ssc.com

There is no guarantee that your questions here will ever be answered. You can be published anonymously - just let us know!

### cd-writing mini-howto

Answer By Chris Coyle

> I found the "CD-Writing with an ATAPI CDR Mini-HOWTO" (http://www.linuxgazette.com/issue57/stoddard.html) very helpful. Thank you.

> Here are a couple of suggestions which other readers who are interested in the same subject may find useful.

> 1. (very minor) I think it should be `/etc/modules.conf` not `/etc/conf.modules`
> 2. I just discovered that the ide-scsi module in kernel 2.2.17 (from RH rpms I just DL'ed), either has a big problem, or else it is significantly incompatible with previous kernels.

> Here's what happened:

> I DL'ed and installed the RH rpms for kernel 2.2.17-14. These were recommended in a security advisory. I kept my previous kernel (2.2.16) installed just in case, adding a new section to `/etc/lilo.conf` by copying the previous one, mutatis mutandis. Then I ran lilo and rebooted. At first everything appeared to be OK with the new kernel, but then I tried to mount my cd-rom and it failed, giving the message

>     mount: wrong fs type, bad option, bad superblock
>     on /dev/cdrom or too many mounted filesystems

> While I was searching for the cause of this I remembered that I had set up my cd-recorder to use ide-scsi.

> My regular cd-rom reader is hdc and the cd-recorder is hdd. Following the directions in your mini-howto, I had inserted

> > `append="hdd=ide-scsi"`

> and this I had copied faithfully into the new 2.2.17 section. When I removed it and rebooted, I found I could mount the cd-rom again. Then I put the line back in and rebooted.

> This time I looked at what scsi devices were detected. Eureka! By looking at dmesg and also by using "cdrecord -scanbus" I discovered that the ide-scsi module had taken over both hdc and hdd, even though I requested only hdd. I asked for help on comp.os.linux.misc and within hours someone else confirmed the same thing, namely

> "...if you have two devices on an IDE channel, and one of them is under ide-scsi emulation, it's better to treat both of them as if they were under ide-scsi emulation.

> I don't know if this is due to a an error or a design change, but the work-around was quite straightforward.

> The only tricky bit was that I wanted to be able to boot 2.2.16 so I had to devise a way to make both kernels boot up in a state where they could use the same devices and configuration files. My solution is as follows:

> 1. Change the lines in `/etc/lilo.conf` to

>    > append="hdc=ide-scsi hdd=ide-scsi"

>    in both kernel sections.
> 2. Move the `/dev/cdrom` link from hdc to scd0.
> 3. Change the scsi configuration for the cd-recorder in `/etc/cdrecord.conf` to 0,1,0 (since it is now the second scsi host).

> After all that I am finally back to the point where I can mount the cd-rom and use the cd-recorder, with either 2.2.16 or 2.2.17 kernel.

##### This page edited and maintained by the Editors of Linux Gazette Copyright © 2001
Published in issue 65 of Linux Gazette April 2001

###### HTML script maintained by Heather Stern of Starshine Technical Services, http://www.starshine.org/

| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 |