Subject: Re: Network boot?
To: None <port-vax@NetBSD.ORG>
From: Lloyd Parkes <>
List: port-vax
Date: 04/14/1996 14:40:09
> NetBSD/vax does not currently support root & swap over NFS. 

How come an NFS root isn't supported? I can understand the swapper not being 
able to cope with NFS yet, but what's so special about the root?

> It should be possible to mop-load a kernel, but I haven't thought
> so much about it. 

Since I have a diskless Vax, I have been working on booting via MOP. I don't 
have (m)any docs, but I have had some success.

There seem to be two main problems with MOPing a kernel. 1) the kernel file is 
in the wrong format, and 2) the kernel expects the processor environment 
(memory, registers etc) to be set up in a particular way when it is started. I 
haven't dug deep enough to confirm #2.

I have written a small program to take care of #1. It just replaces the a.out 
header with one more in line with what the MOP daemon expects, and then it 
pads out program segments that need padding. I have succesfully downloaded the 
boot program using this system, and the boot program executes flawlessly until 
it decides that it doesn't know how to boot. 

I think my initial fix for #2 will be to hack together some custom start up 
code for the kernel. 

> I also think that there can be a hard nut to crack to get UCX
> act as NFS-serversystem for netbooted machines, but I don't know.

That is what NetBSD/sparc and NetBSD/i386 are for ;-)