[BBLISA] MBR that reboots machine

[John Stoffel]

Alex> We need a MBR that reboots the machine. Surely this must exist?

Huh?  

Alex> Our systems boot from the network. If, after a power outage say, that 
Alex> does not work, the BIOS goes on to boot from the local HD. Since the 
Alex> local HD has no OS on it, the boot sequence ends and the machine sits 
Alex> forever waiting for manual intervention.

Ah... so you have a crappy BIOS that doesn't loop endlessly.  Or can
you not remove the HDD from the boot list as well?  Is this in a mix
of systems?  

Alex> If the local HD had a MBR that caused the boot process to start
Alex> over again, then our machines would retry network booting
Alex> forever, until the network boot servers (and all switches along
Alex> the path to them) were up again.

Can't you put your PXE server on a UPS so it will ride out power
outages, even if the other boxes don't?  This way there will be
something alive to respond to reboot requests. 

Alex> I have googled extensively for this, I have found assembly
Alex> source code for the standard Windows MBR, and I think I have
Alex> seen explanations on how to get a machine to reboot in assembly,
Alex> so I may attempt to compile my own bit of code, but it seems
Alex> likely that someone else has done this before.

Have you looked at the syslinux stuff maybe?  Just a small bootloader
that calls into the BIOS reboot vector might be all you need if you
can work with that base.

John