loader: distinguish NFS versus TFTP boot by rootpath
The current bootp/dhcp code is attempting to use option 150, however, the standard pxe request does not include option 150, in some system the option 66 is used - but not always. After long discussions, the simplest possible option was agreed: make distinction based on rootpath value - if it is in form ip:/path, then use NFS, otherwise TFTP.
FreeBSD update: https://svnweb.freebsd.org/base?view=revision&revision=317886
Dan did point out good point:
"In the FreeBSD report is this: "But there is one limitation - only one tftp server in network to provide loader and everything else. Does enybody use more than only one?"
This question needs to be answered in illumos-land."
Well, there is this tiny "but" -- in both worlds, there actually is not possible more than one tftp server, due to the few facts:
1. even as the option 150 does allow list of ip addresses, only one is read in current code.
2. the rest of the code has no support to walk and probe the list of tftp server ip's.
So the background of that question is not about if anyone currently does use more than one tftp server, but rather, should such support be built.
I think, right now we shall leave this question unanswered - we can always get back to it later.