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## <a name="Live_CD"> Live-CD </a>
It would be nice if we had a bootable Hurd Live-CD like Knoppix. This could be use by those who want to try out the Hurd before they commit to installing it on their hard disks. And a bootable Hurd CD would enable us to have a native installer instead of relying on Linux. Please add comments and suggestions.
Here's an outline of the things that need to be done.
* We need to be able get a bootloader for CDs
* This isn't much of a problem. I've already been successful (see below) in using grub and El-torito HD emulation to boot gnumach off of a CD. There may be some minor tweaking of grub code necessary to detect which device to use for booting (instead of having the user select which device (hd0,hd1,etc.) from the grub menu).
* We need a bootstrap filesystem translator
* This would be something like a statically linked iso9660fs translator. Compiling a statically linked iso9660fs translator is easy enough, though it doesn't boot. I don't currently know whether this is because the translator was never meant to be a bootstrap filesystem, or if there is a simple bug which has never been flushed out because the translator has never been used at boot time before. I've had trouble debugging this problem because I haven't yet figured out a way to use a remote gdb with gnumach. Theoretically you could use the "boot" command to overcome this problem, but "boot" for me mangles the terminal and exits in different manner than an actual boot.
* We need a ramdisk to enable write access
* I think we could fake this with Farid Hajii's [memfs](http://www.fprintf.net/hurd/) translator and writing an ext2 filesystem to it. From the mem-fs README...
> memfs-1 is a translator that provides a memory-based file of fixed size. This file can, just like bigfile, contain a regular filesystem.
* * We could set a mem-fs translator anywhere on the CD you needed write access, including having softlinks to the contents of the root directory and chrooting to this new directory.
* * For a quick and dirty memfs, you can do it right now with the following commands:
> touch ./ramdisk
> touch ./tmpfs
> settrans -a ./ramdisk /hurd/storeio -Tcopy zero:50M
> /sbin/mke2fs ./ramdisk
> settrans -a tmpfs /hurd/ext2fs ./ramdisk
> fsysopts --writable ./ramdisk
> cd newfs
> touch somenewfile
>
> > > Here we use two files ramdisk, and tmpfs that are already created on a readonly file system. For illustration purposes, they are touched beforehand. We run an active storeio translator on the ramdisk file to give us 50MB of RAM to work with, and then we make an ext2 filesystem on it. A boot CD would presumably have a ready-made image to copy into the ramdisk, so we wouldn't really need to run mke2fs. After making sure the file system is writable, we mount the image with an ext2fs translator onto tmpfs. And now we're writing files on a writable file system that originated on a readonly filesystem. This idea was first posted in a
> > >
> > > [mail](http://lists.gnu.org/archive/html/bug-hurd/2000-12/msg00073.html)
> > >
> > > on bug-hurd, and it has some drawbacks.
Those are the essentials. Here is a list of the things which would be nice to have for a Live-CD.
* Knoppix like script for starting up X
* DHCP support for easy network setup
* Knoppix like script for installing to the hard drive
* (add your favorite feature here)
Here's a mailing-list [thread](http://lists.debian.org/debian-hurd/2003/debian-hurd-200308/msg00172.html) discussing some of these issues.
-- [[Main/GregBuchholz]] - 21 Oct 2003 -- [[Main/NagromNamreh]] - 29 Jan 2004
----
<a name="gnumachcd">Recipe for bootable gnumach CD</a>
In my attempts to get a bootable CD for the Hurd here's the recipe I followed, your's will be similar. I needed a grub-0.92 with a patch from...
<http://alpha.polynum.org/misc/>
...and I needed the version 1.16 of mkbimage (I don't exactly remember where I got that from). You can grab a copy of...
<http://sleepingsquirrel.org/hurd/hurdcd.iso.gz>
...which is a gzipped bootable \*.iso with the copy of the patched grub and the version of mkbimage I used. Here's the recipe I followed (under linux).
mkdir ./2.88floppy
mkdir ./isodir
cp grub/* 2.88floppy/boot/grub/
cp grub/* isodir/boot/grub/
cd 2.88floppy
tar -cf ../floppyimg.tar *
cd ..
mkbimage -f floppyimg.tar -t 2.88
cp 2.88.image isodir/
mkisofs -r -b 2.88.image -c boot.catalog -o hurdcd.iso isodir/
cdrecord -v speed=4 dev=0,0,0 -data hurdcd.iso
...That was the recipe for using a floppy image. If you use the "-t hd" switch of mkbimage, you'll get an ext2fs El-Torito HD emulation image that can be any size (I've got one here 300+ MB). You then can use "root (hd0,0)" in grub to boot something. Also, invoking mkbimage with no parameters will give you some additional help messages.
-- [[Main/GregBuchholz]] - 05 Nov 2003
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