[syslinux] Large Floppy Images

Bernd Blaauw
Thu, 12 Apr 2007 10:31:33 -0000

Tom Mahoney (syslinux-emails) schreef:
> Bernd Blaauw wrote:
>
Syslinux mailing list has the annoying habit of a 'reply' being sent to
the author of the message by default, rather than sending to the mailing
list as default.
Don't know if that was your intention. I tend to 'fix' this by
deleting
the 'to' field and changing 'cc' into 'to'
:)
> The image did work and booted just fine. Where Freedos is concerned I
> would like a install image to boot from based off of the stable 1.0
> release it hit recently and it's not clear googling around that there
is
> an official one yet.
>
Indeed, only a bootable CD is available, using Isolinux. For older
machines, there's Smart Boot Manager,
and a diskette image (no idea if it's also updated to FreeDOS 1.0 files)
available at
http://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.0/fdboot.img
> Also why would the bootsector not be compatible with my goal of
> combining the three images into one? The idea is simply to take a image
> of the first disk and increase it's size to 5, 8, or 10 megs. Mount the
> image and copy the files from the second and third disk. I want to be
> able to have one image with all files so obviously no disk swapping but
> a single image large enough to fit all files and install from.
>
Most operating systems only contain bootsectors for the specific OS
itself, not for likewise operating systems.
Thus, the FreeDOS bootdisk expects a system file called KERNEL.SYS
rather than IO.SYS or MSDOS.SYS
(or WINBOOT.SYS for all I care). I thought I'd read you intended to
merge the MSDOS disks, which means you're best off
starting with a proper MSDOS bootdisk, then expanding it, then inserting
the files from the remaining disks.

> "Non-System disk or disk error"
>
> The new error message I also get in dosemu when trying to boot from it
> as a virtual floppy:
> This is not a bootable disk.  Please insert a bootable floppy and
> press any key to try again ...
>
improper bootdisk then. Adding a DOS bootsector under Linux on an empty
disk image doesn't seem to be easy,
I remember some PERL script being used to implement a FreeDOS bootsector
for example.

Also, some FreeDOS people have worked on creating opensource bootsectors
that can boot MSDOS 3.3-7.00 and MSDOS-7.10-FAT16.
Win95/98 on FAT32 hasn't succeeded yet. No idea if that special version
of SYS is still available anywhere.
> I'll take a look but I'm curious how I would use that to solve my
> problem. Wouldn't I still need a bootable large floppy image that could
> fit the file decompressed by the ramdisk driver?
>
have a DOS system, load XMS driver, load ramdisk driver, use SYS on this
ramdisk that has (super-)floppy geometry, then add files,
then make a disk image of the ramdisk using a program like 'dd' or
diskcopy for example.
The resulting image should be put on your bootcd or PXE server or
whatever you intend.
> This leads me to a question I have to anyone who could answer. I can
> boot a linux kernel and pass it a initrd to create a ramdrive from. Can
> this also be accomplished with memdisk and a dos floppy image? Can a
> second file be passed to be accessed by the first?
>
Nope. Traditional way is have a bootdisk image, then load some drivers,
and mount a second disksource.
On that second disksource, you might have to mount another disk for
example. I doubt something like the MSDOS installer can handle that.

> I have winimage installed and I am not sure how I would create a image
> bigger than 2.88 to fit all the files.
>
I know it's possible, just not done it except for reading in a bootable
USB stick.

> That sounds real nice. Do you know how to create one of that size that
> boots with msdos or where I could download one? Does anyone know how.
> This sounds just like what I need. Again why would the msdos bootsector
> not be compatible with a floppy image larger than 2.88? I know freedos
> can handle 2.88 can msdos? Not all of these questions are directed right
> at you but to anyone who can answer. Thank you to all who have helped so
> far. =)
>
No idea how to recreate. I got the file contents but not the bootable
image file (file + bootsector) on my USB stick.
I would have to look up one of my outdated 'drivers+OS' cdroms but not
much chance I can find one of those again.
(it had Win2k drivers and operating systems like Knoppix, MSDOS,
ReactOS, FreeDOS and Win2000/XP on a single disk)

Bernd