[CentOS] force a PXE boot

Wed Jul 26 18:04:15 UTC 2006
Tom Brown <tom at ng23.net>

> that depends on the BIOS of your system; it's not an issue that CentOS 
> can (easily) deal with.  some Dell servers have a utility that you can 
> use to change BIOS settings from within the OS, but i can't speak to how 
> well it works.
> 
> here's how i solved a related problem when setting up a lab of machines 
> that would be PXE-booting to reinstall themselves without an admin at 
> the console:
> 
> 1) in the BIOS, set the boot order to PXE,HD (you can put CD/floppy/USB 
> before HD if you want, but PXE must be first)
> 2) set up your TFTP server such that the default boot target boots from 
> the system's hard drive (use the "LOCALBOOT" option as described here: 
> http://syslinux.zytor.com/faq.php)
> 3) created another PXELINUX configuration that performs a network boot 
> and give it a name that corresponds to either the machine's MAC address 
> or the machine's IP address (as described here: 
> http://syslinux.zytor.com/pxe.php#config)
> 4) if you're using the PXE boot to kickstart the machine, add a line to 
> the %post section of your ks.cfg that will ssh to the TFTP server and 
> move aside the PXELINUX config file with the machine's MAC/IP address 
> (you can make this process as simple or complicated as you need)
> 
> if you follow these steps, then the machine will PXE-boot when the 
> special config file is in place, kickstart itself, and then move the 
> special config file aside; when it next boots, the TFTP server won't 
> find the special config file, so it'll use the default config file, 
> which tells the machine to boot from the local hard drive.
> 
> does this make sense?
> 
> -steve
> 
> p.s. there are other ways of having the machine "phone home" to the tftp 
> server besides using ssh; one of my colleagues did it with a little php 
> script.  alternately, you could have a script running on the TFTP server 
> that watches the logfile for evidence of successful PXE boots and uses 
> that information to move aside the special config file.

thanks - these are Dells yes so i'll give this a shot

cheers