How to Copy Kernel Image to a CD?

Lucinda · 05-25-2004, 07:23 PM

My kernel image is too big to copy onto a floppy disk, so I'd like to copy it onto a CD. I've tried dd if=/boot/vmlinuz of=/dev/fd0 but it won't copy onto the CD because it's read-only. I guess I'd have to go through cdrecord, but how do I do that with the "dd" command?

Thanks,
Lucinda

Bruce Hill · 05-25-2004, 07:33 PM

Welcome to LQ!

You don't do that with the dd command. Check out this link
http://www.linuxquestions.org/questi...hreadid=169240
fancypiper has all the info you need about burning a CD right there.

Lucinda · 05-25-2004, 07:49 PM

I tried the command dd if=/boot/vmlinuz of=backup.iso, and while it does create file, k3b and xcdroast won't let me burn it because they say it's not a valid .iso file.

Any ideas what I could try next?

Bruce Hill · 05-25-2004, 07:55 PM

Quote:

Originally posted by Lucinda
I tried the command dd if=/boot/vmlinuz of=backup.iso, and while it does create file, k3b and xcdroast won't let me burn it because they say it's not a valid .iso file.

Any ideas what I could try next?

I don't use gui's to burn, so I can't offer advice on how to make 'em work, but

Code:

cdrecord -v speed=<burning speed> dev=<your device> /path/to/foo.iso

will burn that iso file to a cd from a console (as root, of course).

You'll also find some more links in fancypiper's thread to some info about cd writing.

EDIT: /me thinks you did the wrong thing ->

Code:

# Generate an ISO from a directory.
mkisofs -vrTJUV "Label" -o foo.iso /path/to/directory
# Generate an ISO from a CD
dd if=/dev/cdrom of=foo.iso

Lucinda · 05-25-2004, 09:14 PM

Are you sure that will create a kernel image on a cd that I can use to boot with? I've tried what you've suggested and it doesn't seem to create the proper files.

Have you tried this yourself and been able to boot from it?? I'm really looking for information from someone who has actually created a cd with the kernel image on it and has been able to boot from it (in the same way you can boot from a floppy).

Bruce Hill · 05-25-2004, 09:54 PM

You failed to mention you wanted to boot with it. What was wrong with the
instructions jong357 gave you in your other thread on this subject?

Lucinda · 05-25-2004, 10:03 PM

He's got a lot of good information but since I'm new at this I don't see how I can adapt it to create the same kind of boot cd that "makebootdisk" creates. As I've mentioned, my kernel image is too large to fit on a floppy. I've searched all over the web for information on how to create a bootable cd with the kernel image on it, but I haven't been able to find advice from anyone who's actually done it. Maybe I'm too optimistic in thinking it can be done...or maybe the users who've actually done it don't read these forums!!

Bruce Hill · 05-25-2004, 10:34 PM

I'm with you - it's frustrating to have a question that no one seems to be able to
answer, and then some fellers just "take a guess." At first I didn't know you
wanted to boot with it, and wondered why you didn't just copy .config to a disc.

Well, missy, here's what I'll do. I'm rebuilding two comps right now. They'll both
get Slack 9.1 installed. The first is a lappy with no burner, so can't actually burn
the image there - though I can make it and transfer to a USB hd and burn from
this workstation. Then I'll install to the workstation, and on both of these installs
I'll try to burn a kernel image to CD for booting. I don't mind trying jong357's
method. I've watched his posts for a while, and he's delivered some good
advice. Plus, he has a similar Dell Inspiron lappy as the one I'm rebuilding.
NB: I'll be recompiling with 2.4.26, so it may be a day or two before I get
around to it...

Sorry not to have been more help - yet. You might also try http://lkml.org
and see if one of them fellers has either posted something, or will tell you.
I tried to get there and they're replacing hardware - it's down at the moment.
Please post back if you figure it out so's I won't have to spin my wheels. ;-)

Lucinda · 05-25-2004, 11:27 PM

Thanks, that would be great. Yes, I did use jong357's advice on making the rescue disk and that's worked fine. I was just hoping to get a copy of the kernel on a cd. I've been sifting through the bootdisk HOWTO, so I might be able to figure it out from there. I'm just surprised that there's not some good documentation out on the net from others who have actually done it.

Regards,
Lucinda

Bruce Hill · 05-26-2004, 03:07 AM

I heard from my bud from NZ, and he says, "basically it's like making an image
file of a 2.88MB floppy, and burn that using the el-torrito method." Going down
for a kip now, then I'll do the first Slack install. Maybe sometime tonight I can
recompile the kernel (if the wife doesn't take me shopping again) and try that
method tomorrow. We'll get it working sooner or later.