Subject: Re: bootp & the DEC alpha as1200
To: Stephen M Jones <>
From: Michael L. Hitch <>
List: port-alpha
Date: 03/15/2002 07:47:51
On Fri, 15 Mar 2002, Stephen M Jones wrote:

> >   I believe that will cause you problems once you manage to get netboot
> > loaded and running.  Netboot needs rp to nfs mount the path to the kernel
> > file.
> Are you sure? the 'netbsd.gz' image is the install kernel which is supposed
> to be an all incompassing image.  I'm really not interested in having a
> network filesystem, just something in memory so I can at least boot a
> system to diagnose local disk issues.  

  As I understand it (which may be incorrect), the SRM uses bootp to get
the bootfile name and the IP address of the tftp server.  It then uses
tftp to load the bootfile (normally netboot).  Netboot then uses bootp get
get the root path for the kernel and does an NFS mount of that root path
and looks for the various kernel files (or the file specified on the
SRM command line) there.

> >   I can't see any obvious reason netboot isn't getting loaded.  One thing
> > that could be done is to run tcpdump and capture all the traffic to/from
> > bjork and see if it's even attempting a tftp transfer.
> That was a bit revealing:
> 06:46:05.407504 >  xid:0xc084af5c secs:4 file ""[|bootp]
> 06:46:05.424178 > bjork.bootpc:  xid:0xc084af5c secs:4 Y:bjork sname "otaku" file ""[|bootp]
> Apparently 'file' isn't getting set somewhere.  My understanding of bootp
> is that the server tells the client what file to tftp first (bootfile)
> and then the client will tftp the file that is on the 'boot' srm
> command line.

  Did you specify a larger capture size for tcpdump?  The default will be
too short to pick up useful information.  [I think the "|bootp" string
indicates there was more expected data beyond the packet tcpdump got.]

Michael L. Hitch
Computer Consultant
Information Technology Center
Montana State University	Bozeman, MT	USA