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PXEBOOT(8)             DragonFly System Manager's Manual            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 Ethernet-
     equipped Intel motherboards.  PXE supports DHCP configuration and
     provides low-level NIC access services.  The pxeboot bootloader retrieves
     the kernel, modules, and other files either via NFS over UDP.  In
     combination with a 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 sample
     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 "boot/pxeboot";
                  range 10.0.0.10 10.0.0.254;
                  option root-path "10.0.0.1:/netbootroot";
           }

     pxeboot defaults to a conservative 1024 byte NFS data packet.  This may
     be changed by setting the nfs.read_size variable in /boot/loader.conf.
     Valid values range from 1024 to 4096 bytes.

     pxeboot recognizes next-server and option root-path directives as the
     server and path to NFS mount for file requests, respectively, or the
     server to make TFTP requests to.  Note that pxeboot expects to fetch
     /boot/dloader.rc from the specified server before loading any other
     files.

     pxeboot uses /boot/kernel.BOOTP and /boot/loader-bootp.conf instead of
     /boot/kernel and /boot/loader.conf.  Note that the TFTP version
     pxeboot_tftp(8) uses the standard boot loader files.  The NFS version
     uses different files to allow BOOTP boots via NFS to be overloaded onto
     the same directory structure as a normal boot, though many other changes
     would have to be made to actually make that work.  However, this is more
     for historical reasons.  Current day PXE boot code can handle complex
     root-path specifications allowing the root image to be contained in a
     sub-directory of the NFS export.

     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 manufacturer for
     their latest stable release.

     For further information on Intel's PXE specifications and Wired for
     Management (WfM) systems, see http://developer.intel.com/ial/wfm/.


FILES

     /boot/kernel.BOOTP                    Default kernel for pxeboot.
     /boot/defaults/loader-bootp.conf      pxeboot configuration file -- do
                                           not change this file.
     /boot/loader-bootp.conf               pxeboot configuration file.


SEE ALSO

     dhcpd(8) (net/isc-dhcp42-server), diskless(8), loader(8), nfsd(8),
     pxeboot_tftp(8), tftpd(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>.

DragonFly 6.1-DEVELOPMENT      November 1, 2019      DragonFly 6.1-DEVELOPMENT

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