Preboot Execution Enviornment (PXE) Boot Server

What is PXE?

Preboot Execution Environment(PXE) is a client-server interface that allows computers in a network to be booted from the server before deploying an OS image in local and remote offices, for PXE enabled clients. PXE network boot is performed using client-server protocols like DHCP(Dynamic Host Configuration Protocol) and TFTP(Trivial File Transfer Protocol). PXE will be enabled by default on all computers.

How does PXE boot work?

Before a PXE network boot, the DHCP server/scope Options 66 and 67 should be configured. Refer to this document to learn how to configure different DHCP servers easily. After the client computer is assigned with an IP address, the PXE boot process starts.

PXE boot process - ManageEngine OS Deployer

DHCP configuration process

  • The client computer sends a 'discover' packet in the form of a broadcast requesting for network configuration. This packet will be received by the DHCP server.
  • An 'offer' packet will be sent from a DHCP server to the client. After analyzing the 'offer', the client will be assigned the network parameters like IP address, subnet mask, etc.

PXE Boot Process

  • The client will notify the DHCP, that it is using PXE boot server. The DHCP server will send the Next Boot Server's IP address(Option 66) and the Boot Filename(Option 67) to the client.
  • The client will contact the PXE boot server and request for the boot files.
  • The PXE boot server will send the boot files to the client through the Trivial File Transfer Protocol (TFTP).
  • In the DHCP server, Options 66 and 67 can be configured under scope or server options. This aids in the loading and launching of the boot files for the client computer.

Note:

  • In Manage Engine OS Deployer, PXE boot server runs as a separate Windows Service, named as 'ManageEngine OS Deployer PXE Server'.
  • To learn more how to configure your DHCP for PXE, click here.