The dhcpd.conf file that we use to assign IP's to slave nodes is stored in CVS
and the working version can be found at medusa:/etc/dhcpd.conf. This file
matches the FQDN of the slave nodes with their MAC addrs. When a slave node
boots, it will actually attempt to configure itself twice via DHCP: the first
attempt is made by the PXE-boot rom included with the motherboard's integrated
ethernet controller; the second is attempted by the OS on boot up.
PXE-boot -- we use the boot image capabilities of DHCP, along with the
integrated PXE-boot rom for installing the OS on slave nodes. When a slave
node boots, the BIOS on the motherboard sends a DHCP broadcast packet, asking
for config info (IP config info, ie addr, netmask, gateway; as well as boot
image file location). The boot room looks for a boot file after receiving it's
IP info; if no boot file is found, the node then attempts to boot from CD, then
HDD. See the doc "Cloning a node" for more details.
OS-boot -- after the PXE-boot completes, a slave node boots from the
boot-loader installed in the MBR on the primary master HDD. This by default
boots a linux installation that attempts to config various info via DHCP.
This document does not attempt to list all options handled by the DHCP server.
Please refer to the dhcpd.conf file located in CVS for a full listing.