I believe that all bootable CDs have floppy disk images used by BIOS routines to boot from. You need to create a bootable floppy image which is then copied in it's raw format to CD. Kernel of course needs to point to the correct device for root device, either RAM disk, CD, or HDD. There are scripts to do this somewhat automaticaly I believe but can't remember where I saw them. I know that I need to point to a bootable floppy image with mkisofs in order to create a bootable CD dowloaded from the internet. That's true for Debian, Redhat, etc. disks. I have short notes in a form: You must have an 1.44 MB bootable floppy-disk. Create an exact image of this floppy-disk by issuing the command dd if=/dev/fd0 of=boot.img bs=18k Place this floppy image into the directory holding the collection of your files (or into a subdirectory of it, just as you like). Tell mkisofs about this file with the option '-b' and also use '-c'. For details read the file README.eltorito in the mkisofs-distribution. I use gcombust GUI tool to burn bootable CD images or create backups of important files and directories in my home directory. By the way, I do not backup everything, it takes too much space and many files can simply be downloaded from the internet. I do copy two files home.tree and home.treed which contain names of all files and directories in my home directory. You can replace a CD image with a HDD partition for testing. That way you can test bootable CD images without burning bad CDs. Old 1GB HDD would be enough for such experimenting. You can create your own distribution that way or cleanup existing one (Redhat for example) to include minimal number of files relevant to your use or hardware. There is a nice Linux distribution knoppix that runs out of a CD. After bootup it can store the configuration on a hard drive for future use and has many options for bootup as well as run. It's hardware detection is very good and includes many sound cards, USB devices, etc. You can play test music files or connect to the internet and listen to streaming data. It's my understanding that it could be used for installing Debian distribution on a hard drive but haven't tested that. Knoppix normaly starts KDE for GUI access to the system. It is possible however to override that at boot prompt. Saying that I believe Knoppix would be a good starting point for a CD that meets your needs. You could select different startup scripts to do things relevant to your distribution. Replacing GUI with specific utilities and files it would be possible to probe for special devices during boot process installing modules for them. It might be possible to dump a sound file to audio device early in the boot process to suggest what's being detected and what needs to be done next to proceede from there. The best way to learn about this is to have a bootable CD image on a hard drive, loop mount it to a directory where you can look into files make changes, delete unnecessary files or add new things. You could export that as NFS files and have them loaded on another system over the neet. Old PC with floppy would be all that's needed for testing your "new distribution". Basic bootup process is a minor thing. What's more critical is detecting all devices or have their drivers ready when they come online. Due to wast number of PCs out there it's hard to include everything but good modularised kernel can detect major devices without problem. I use debian and RedHat install disks for emergency situations and see no need for special rescue disks. Of course that fine for sighted people. For others it would be nice to modify those to provide additional means for communication through serial and other ports by default. There are too many possibilities to list here but you get an idea. While discussion could be taken offline it's my belief that those not interested can simply ignore or delete it while others might add usefull ideas if the discussion stays on the list for a while. I'll look for any commands or scripts for creating bootable CDs that you could use and send them to the list. I'm sure others have them already so some search on the net is needed. I'm in the process of home/DSL move so I can't respond to email right away since my server is in my friend's office. On Mon, Mar 03, 2003 at 07:27:46PM +0000, Karl Dahlke wrote: > This is long, but definitely "on topic", so please read. > > You may have noticed that the newest computers don't have floppy drives. > They boot from CD rom. > Therefore, we need talking rescue CDs. > > Yes, there are some out there, but let's say we want to build our own, > with our adapters, our utilities, etc. > How can this be accomplished? > I'm looking for advice/ideas. > Here are the options as I see them. > Some of these may not even be possible; I don't know. > > (A) Place your mini distribution, with adapter and utilities etc, > into a ram disk or a loop-accessible file. > Use lilo to replace the first 512 bytes, thus creating a boot disk > that is also a Linux disk. > Then burn this out to a CD. > I know this works with floppies, but don't know about CDs. > Can you make a bootable linux file system this way? > Does the file system have to cover the entire CD, or can it be smaller? > My system, that makes me happy, is 80 meg, > so it's a shame to have to manipulate and burn all 670 megs. > And, how do you set the root device, since some CDs are on hdc > while others are on hdd. > Guess wrong, and Linux doesn't come up at all. > Also, some CD players require weird drivers that might not be on my distro. > > (B) put a bzImage at the base of the CD so LInux boots > directly, no boot loaders involved. > It then sucks in a large ramdisk. > Maybe it's 30 or 40 meg. > Today's computers can handle that. > You've got all your utilities, everything you need, > in memory. > You don't have to keep the CD spinning, in fact you can take it out completely. > Now mount your hard drives and go to work. > Also, no need to copy and remount directories in tmpfs, > like /tmp and /etc and /home, so they can be writable. > Everything is writable, because it's all in memory, and no longer on CD. > And I don't have to set the root device. > I like this approach, but if you have an older computer with less then 64 meg, > it's probably not going to work for you. > That's the only down side I guess. > Other than that, it's very simple and convenient. > > (C) A hybrid. > Put bzImage at the base and suck in a modest initrd, just a few megs. > It wakes up, looks around, figures out where the CD is, > loads the necessary drivers, mounts the CD, > say under /usr, and gives you access to the rest of the utilities that don't > fit in memory. > This is the most complicated of the three, but the most general and flexible. > Is it possible, btw, to have a linux file system on a CD, > that you can mount, that doesn't start at the beginning? > It would have to start past the bzImage and past the initrd image - > and I don't know if that can be done. > > And perhaps there are other ways to implement this that I haven't thought of. > > Please give me your ideas. > If you can give a detailed procedure on how to make such a disk, > that's even better; > though you might want to mail that to me off line, eklhad@comcast.net, > so as not to clog up this list too much. > > Thank you, > Karl -- Rafael _______________________________________________ Blinux-list@redhat.com https://listman.redhat.com/mailman/listinfo/blinux-list