pxeboot(8)

NAME

pxeboot - Preboot Execution Environment (PXE) bootloader

DESCRIPTION

The pxeboot bootloader is a modified version of the system

third-stage
bootstrap loader(8) configured to run under Intel's Preboot

Execution
Environment (PXE) system. PXE is a form of smart boot ROM,

built into
Intel EtherExpress Pro/100 and 3Com 3c905c Ethernet cards,

and Ethernetequipped Intel motherboards. PXE supports DHCP configura

tion and provides low-level NIC access services. The pxeboot bootloader

retrieves
the kernel, modules, and other files either via NFS over UDP

or by TFTP,
selectable through compile-time options. In combination

with a memory
file system image or NFS-mounted root file system, pxeboot

allows for
easy, EEPROM-burner free construction of diskless machines.

The pxeboot binary is loaded just like any other boot file,

by specifying
it in the DHCP server's configuration file. Below is a sam

ple configuration for the ISC DHCP v2 server:

option domain-name "example.com";
option routers 10.0.0.1;
option subnet-mask 255.255.255.0;
option broadcast-address 10.0.0.255;
option domain-name-servers 10.0.0.1;
server-name "DHCPserver";
server-identifier 10.0.0.1;

default-lease-time 120;
max-lease-time 120;

subnet 10.0.0.0 netmask 255.255.255.0 {

filename "pxeboot";
range 10.0.0.10 10.0.0.254;

}

pxeboot recognizes next-server and option root-path direc

tives as the
server and path to NFS mount for file requests, respective

ly, or the
server to make TFTP requests to. Note that pxeboot expects

to fetch
/boot/loader.rc from the specified server before loading any

other files.

In all other respects, pxeboot acts just like loader(8).

As PXE is still in its infancy, some firmware versions may

not work properly. The pxeboot bootloader has been extensively tested on

version 0.99
of Intel firmware; pre-release versions of the newer 2.0

firmware are
known to have problems. Check with the device's manufactur

er for their
latest stable release.

For further information on Intel's PXE specifications and

Wired for Management (WfM) systems, see http://developer.in

tel.com/ial/wfm/.

SEE ALSO

loader(8)

HISTORY

The pxeboot bootloader first appeared in FreeBSD 4.1.

AUTHORS

The pxeboot bootloader was written by John Baldwin

<jhb@FreeBSD.org> and
Paul Saab <ps@FreeBSD.org>. This manual page was written by

Doug White
<dwhite@FreeBSD.org>.

BSD May 1, 2000

BSD