Syslinux - Dec 2003 - 2 disks boot

Hi all!
It's my first message on this ML.
I just installed Fedora Core and I had a small problem... kernel +
initrd do not fit in a 1.44 disks...

I looked at documentation and at code (kernel.inc) and I saw that
syslinux
- load kernel
- load initrd
- boot kernel
So perhaps a small workaround for above problem should be to add a
configuration to initrd (ie initrd=@initrd.img) to just ask to replace
the disk, and wait a key press and then load initrd from second floppy.
I know some changes are required (remove '@' from kernel command line,
test if disk/initrd is present and if not ask for correct disk) however
that doesn't seem too complicated...
At the moment I'm quite busy but if you want I can propose a patch (I
hope when next year starts)...

freddy77

ZIGLIO Frediano wrote:
> Hi all!
> It's my first message on this ML.
> I just installed Fedora Core and I had a small problem... kernel +
> initrd do not fit in a 1.44 disks...
> 
> I looked at documentation and at code (kernel.inc) and I saw that
> syslinux
> - load kernel
> - load initrd
> - boot kernel
> So perhaps a small workaround for above problem should be to add a
> configuration to initrd (ie initrd=@initrd.img) to just ask to replace
> the disk, and wait a key press and then load initrd from second floppy.
> I know some changes are required (remove '@' from kernel command
line,
> test if disk/initrd is present and if not ask for correct disk) however
> that doesn't seem too complicated...
It doesn't seem complicated, but unfortunately it's a pretty hard 
assumption in syslinux that storage is always online.  However, your 
particular suggestion is a bit more constructive than a lot of things 
I've seen in the past; explicitly telling syslinux which particular disk 
needs to be inserted would significantly make this easier.

Thus, a filename syntax like 2:initrd.img for "initrd.img on disk 2" 
would be quite a bit less pain than having a list of files and their 
disks, which has otherwise been the main alternative.

This definitely deserves some thinking about.

	-hpa

> 
> ZIGLIO Frediano wrote:
> > Hi all!
> > It's my first message on this ML.
> > I just installed Fedora Core and I had a small problem... kernel +
> > initrd do not fit in a 1.44 disks...
> > 
> > I looked at documentation and at code (kernel.inc) and I saw that
> > syslinux
> > - load kernel
> > - load initrd
> > - boot kernel
> > So perhaps a small workaround for above problem should be to add a 
> > configuration to initrd (ie initrd=@initrd.img) to just ask 
> to replace
> > the disk, and wait a key press and then load initrd from second
> > floppy. I know some changes are required (remove '@' from
kernel
> > command line, test if disk/initrd is present and if not ask for 
> > correct disk) however that doesn't seem too complicated...
> 
> It doesn't seem complicated, but unfortunately it's a pretty hard
> assumption in syslinux that storage is always online.  However, your 
> particular suggestion is a bit more constructive than a lot of things 
> I've seen in the past; explicitly telling syslinux which 
> particular disk 
> needs to be inserted would significantly make this easier.
> 
> Thus, a filename syntax like 2:initrd.img for "initrd.img on disk
2"
> would be quite a bit less pain than having a list of files and their 
> disks, which has otherwise been the main alternative.
> 
> This definitely deserves some thinking about.
> 
> 	-hpa
> 
You are right, ':' it's better that '@'..
Before start coding it's however better to plan changes. Thinking at
future perhaps most easy and simple syntax should be

"n-m:file.ext"
or 
"n:file.ext"

So we have a range of disks... for future possible extensions. Also it
would be glad if images get numbered as perl do, ie if we have
"initrd=2-4:initrd.img" will have:

initrd.img (disk #2)
initrd.imf (disk #3)
initrd.imh (disk #4)

Or using numbers (initrd=2-4:initrd.i00)

initrd.i00 (disk #2)
initrd.i01 (disk #3)
initrd.i02 (disk #4)
...

The problem is perhaps image sizes (difficult to compute from first
disk)... I didn't watch so deeply ldlinux code... However the first
change I want to write is
- support "n:initrd_name.ext" syntax where n is a digit
- do not support multi-disk and kernel not on the first disk
- support for different disks size/format options reloading first sector
(optional??) This should be sufficient even for 2.6 kernel...

freddy77