User manual

Etherboot User Manual

1.4. Acknowledgments and Thanks

Thanks to Markus Gutschke who wrote the ﬁrst version of this document, and to all the people who have

contributed information and corrections to this document.

For a list of people who have contributed substantially to the code, please see Section 10 section.

2. Introduction to Etherboot

2.1. What is Etherboot?

Etherboot is a software package for creating ROM images that can download code over an Ethernet

network to be executed on a computer. Many network adapters have a socket where a ROM chip can be

installed. Etherboot is code that can be put in such a ROM. Etherboot can also be booted from ﬂoppies

(mainly for testing purposes but some people have been known to use this all the time) and hard disk, as

a LILO/SYSLINUX compatible image, or from a hard disk partition, or via PXE.

Etherboot works on the x86, Itanium and Hammer architectures. It has not been ported to other platforms

yet. Typically the computer is diskless and the code is Linux or FreeBSD, but these are not the only

possibilities. The code uses the DHCP, tftp and NFS Internet Protocols, amongst others.

For a rather out of date but short talk/tutorial type introduction to what Etherboot does, see my SLUG

talk (../diskless/t1.html).

2.2. License

Etherboot is Open Source under the GNU General Public License Version 2 (GPL2). The license

conditions can be obtained from the ﬁle COPYING in the top directory of the distribution or viewed at

www.gnu.org (http://www.gnu.org/). In particular note that if you are distributing binaries generated

from Etherboot, such as ROMs or ROM images, you must provide or promise to provide the user with

the source. If you have not made private changes to the code, you can do this by pointing the user to the

Etherboot home page (http://www.etherboot.org/), noting the release version of course. If you have made

private changes to the code, then you must distribute those changes too with binary distributions.

The following is not legal advice and you should seek your own legal advice but it is a reasonable

interpretation of the GPL with respect to Etherboot and BIOS code. Installing Etherboot, either as an

extension BIOS or combined in the BIOS chip is mere aggregation. The GPL does not extend to other

works that a GPLed binary is aggregated with on a storage medium. The rationale is this: The BIOS does

not need an Etherboot ROM to function and the Etherboot ROM can work equally well with another

BIOS implementation. Therefore putting Etherboot either on a ROM chip or in the same chip as the

BIOS does not cause the two to become a combined work. Under this interpretation, there is no fear that

you have to GPL your BIOS if you ship Etherboot with your BIOS.

The GPL applies to the whole package but a few ﬁles may be used under other licenses for historical

reasons. See Section 11 for details. Please support Open Source by joining the community and sharing.

See the Etherboot home page (http://www.etherboot.org/) for some ways you can help Etherboot.