[c-nsp] cisco pxe boot support

[Michael Sprouffske]

I'm trying to have my cisco router set the next-server address and the bootfile name.  I see the cisco dhcp server sending that info correctly to the computer but the machine never takes the offer.  If just fails trying to load from pxe.  If I take the pxe server and attach that to the machine via a switch and setup dhcp on the pxe server, the machine picks it up just fine.  I checked the pxe server and all it does is sets the next-server and the bootfile name.  Am I missing something on my cisco 2900 that is prohibiting me from doing this?