[syslinux] Pxelinux/memdisk with XP "MS-DOS" boot disk

[dpetersen55 at new.rr.com]

At 02:27 PM 12/30/2003, you wrote:
>dpetersen55 at new.rr.com wrote:
>>I'm trying to use this universal DOS TCP/IP boot disk available here:
>>http://members.iinet.net.au/~bdriver/bootdisk/
>>It requires an MS-DOS formatted disk created by Windows XP.  It works 
>>great as a floppy but doesn't boot at all with memdisk.  The problem can 
>>be simplified down to just the XP boot disk.  If you make an MS-DOS 
>>startup disk with XP on a floppy, dd the floppy to an image file and try 
>>to boot it with pxelinux/memdisk, it hangs.  It just says "Starting..." 
>>and won't even respond to ctrl+alt+del.  I've booted lots of PC-DOS, 
>>MS-DOS, Linux, and BIOS flash disks with no problems, but this one just 
>>won't run.
>>Any ideas how to debug this?
>
>Is there an autoexec.bat/config.sys or the equivalent on the disk?  If so 
>it might be possible to hit <f8> (is that right?) and single-step loading 
>the drivers one after another.  It's probably HIMEM.SYS or EMM386.EXE or 
>whatever the equivalents are that are causing pain.
>
>Either that or it has the FreeDOS bug and assumes "one disk with EBIOS = 
>all disks with EBIOS" which is incorrect (and won't work with a controller 
>on a card.)
>
>         -hpa

Thanks for the quick response hpa.  It's got a config.sys and autoexec.bat, 
but with the simple case of a fresh XP boot disk they're both empty.  It 
doesn't seem like the traditional MS-DOS boot disk, it is entirely possible 
they're making an assumption somewhere in the boot code which isn't correct 
when loaded with memdisk.  The reason the universal disk I mentioned above 
requires this particular type of boot disk is because it is significantly 
smaller than the old 95/98 disk.