Performing a GRUB based network boot requires a DHCP server that is configured for PXE clients and an install server that provides tftp service. The DHCP server must be able to respond to the DHCP classes, PXEClient and GRUBClient. The DHCP response must contain the following information:
IP address of the file server
Name of the boot file (pxegrub)
rpc.bootparamd, which is usually a requirement on the server side for performing a network boot, is not required for a GRUB based network boot.
If no PXE or DHCP server is available, you can load GRUB from CD-ROM or local disk. You can then manually configure the network in GRUB and download the multiboot program and the boot archive from the file server.
For more information, see x86: Overview of Booting and Installing Over the Network With PXE.