Subject: Re: Netbooting - two stage bootstrapping?
To: Simon Burge <simonb@telstra.com.au>
From: Michael L. Hitch <mhitch@lightning.oscs.montana.edu>
List: port-pmax
Date: 08/19/1998 13:42:24
On Aug 20,  1:17am, Simon Burge wrote:
>      2. The second stage bootstrap uses further information in the BOOTP
>         packet that the console received to find the NFS server and path
>         and retreive the kernel (the file /netbsd). After loading the
>         kernel into memory, it executes it.

  Do you or anyone else have any details on how that second stage bootstrap
would obtain the BOOTP packet information on the DECstation?

> directory (which are in different object file formats!).  With a two
> stage boot (load the network loader, then the kernel), the program in
> /tftpboot would (hopefully!) remain pretty static, and we'd only have to
> update the kernel in the root directory.
> 
> Is there any interest in moving to a scheme like this?

  I'm sure there is, particularly on machines that have problems downloading
the kernel image.

  I have done some work on a two-stage disk boot, and have been able to
create a first-stage loader that loads an ECOFF second stage loader.  [Using
ECOFF would allow the same loader to be loaded from the disk or the
network boot.]

Michael

P.S.  My second-stage loader was also able to load ELF kernels as well as
a.out kernels.


-- 
Michael L. Hitch			mhitch@montana.edu
Computer Consultant
Information Technology Center
Montana State University	Bozeman, MT	USA