Ahhh, sometimes it’s good to know the difference between DE-FACTO and DE-JURE standards.
DE-FACTO means “by default”, and it’s likely that everyone does it this way. Some examples: HP JetDirect (raw tcp port 9100) printing is a de-facto standard of network printing. Common and popular because it works across many computing platforms and it’s simple — so much so that companies have mimicked it.
DE-JURE means “by law”, and this commonly refers to more clearly defined standards that are controlled by a governing body. Like HTTP, FTP are controlled by the IETF.
When these two ideas bump together, boy can it be interesting. Anybody who has done a little research at the IETF site for details on how to PXE boot a PC can tell you it looks like an involved process that requires DHCP, BOOTP, and TFTP (see pxe.ca or Wikipedia for what I’m talking about). Seems like more work than it’s worth.
BUT, LOW AND BEHOLD, Intel, one of the originators of PXE and WfM, and the largest source of firmware for onboard network cards in corporate/business PC systems, decides that all this is complicated, and they make new firmware capable of booting with merely two options setup on the DHCP server and a TFTP server to host the bootstrap image. BUT THEY DON’T TELL A SOUL ABOUT IT. Luckily for me and you, someone figures this out and posts it out there for everyone to see. This person happens to be H. Peter Anvin, working on the PXELINUX project. You can see the details I’m talking about at the FAQ page of PXELINUX at zytor.com. It basically amounts to: For a long time now, Intel’s boot firmwares have not required proxy DHCP or BOOTP. Just set DHCP options 66 and 67 (next-server and filename) to point to your TFTP server, and the bootstrap image you intend to use, and everything works fine.
I hope I don’t look like the type of person who likes to do long division on paper, when a calculator is right next to me.
Frustrating sometimes, really, how a DE-JURE standard can combine with DE-FACTO standard.
