[syslinux] PXELINUX based kickstart query (probably OT)

[Josh Lehan]

H. Peter Anvin wrote:
> Can't be done.  Unfortunately the BIOS considers loading a boot sector 
> (from floppy or from hard disk) to be "terminal" in the sense that it 
> has now booted, and there is no going back.
> 
> This is one of the most unfortunate aspects of the BIOS.

Hmm, would calling INT 18 work?

INT 18 seems to have the meaning of "there's nothing to boot here, move 
along".

In the MBR, an INT 18 will return control to the BIOS.

A good BIOS hopefully will advance to the next device in the boot 
sequence.  A bad BIOS will probably just hang then, with the unfortunate 
"Missing operating system" error message.

It might be worth a try to overwrite some of the code in the MBR of your 
hard drive, to force a call to INT 18, if you don't want to boot from 
that drive.

This differs from INT 19, which should do a full reset of the computer, 
entirely starting the boot sequence over from the beginning.  If INT 18 
doesn't work, to advance to the next boot device, then maybe INT 19, to 
go back to the beginning, might be another way to solve the problem.

Josh