[K12OSN] DHCP and PXE with two different Class of IP

Bert Rolston bert.rolston at clear.net.nz
Sat Dec 9 07:27:46 UTC 2006

Hi David,

That's the kicker.

The K12LTSP internal nic WILL be on the same physical network as the MS
Class B dhcp server.

My gut instinct is to modify K12LTSP to work with the CLASS B

In other words let the MS DHCP server dish out the addresses. BUT as I
have read here in the past, this poses a problem with redirecting PXE
requests to the K12LTSP server. Or has this issue been resolved?

Bearing in mind I might not be allowed to make changes to the MS DHCP
server, I was looking for an alternative. 

Unfortunately, the terminals will be spread ALL OVER campus, not in a
single lab where I could throw in another switch and repatch the lab
machines onto that switch. :-(

So if anyone has run into a similar situation I would appreciates some

At this stage I don't even know the full layout of the network.

Thanks again David, 
and the list.

Bert Rolston

> ------------------------------
> Message: 2
> Date: Fri, 8 Dec 2006 09:00:32 -0500
> From: "David Whitmer" <thewhitmers at gmail.com>
> Subject: Re: [K12OSN] DHCP and PXE with two different Class of IP
> 	address
> To: "Support list for open source software in schools."
> 	<k12osn at redhat.com>
> Message-ID:
> 	<a28861770612080600p19ae4a4ci6e00f024384634a0 at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> On 12/7/06, Bert Rolston <bert.rolston at clear.net.nz> wrote:
> > Thanks John,
> >
> > <snip>
> >
> > But back to the question.
> >
> > So what you were saying earlier is that on the K12LTSP server I set up
> >        - 1 NIC with a Class B address that matches their scheme,
> >          connected to their physical media
> >        - 1 NIC with the standard K12LTSP Class C scheme connected to
> >          the same physical media, through the same switch
> >
> > This should satisfy my customer's criteria.
> >
> > What will the MS DHCP server do when a PXE request comes from the old
> > hardware?
> >
> > I may be answering my own question, as I understand things MS DHCP will
> > ignore the request. Is that the case?
> >
> > As for the LTSP DHCP server, I take it I can tell it to IGNORE any DHCP
> > requests from a host with an MS operating system.
> >
> > Thanks for your time.
> >
> > Cheers,
> > Bert
> >
> Bert,
> As long as the PXE-booting computers are connected to the same
> physical network connected to the K12LTSP server's "internal" NIC, the
> PXE request will stop at that server and not go out to your class B
> network.
> Also, the NIC connected to the class B network will not be running
> DHCP service... the K12LTSP server by default only runs that for the
> internal network NIC.
> In your e-mail, it looks like you're planning to connect both of the
> NICs in the K12LTSP server into the same network switch.  That will
> cause you problems.  The default K12LTSP setup is meant to have the
> server act as a gateway/router between two physical networks, one for
> your thin client (PXE booting) computers, and the other your main
> network.
> David Whitmer
> Director of Media & Technology
> Calvary Schools of Holland (Michigan)
> web: www.calvaryschoolsholland.org
> email: thewhitmers at gmail.com

More information about the K12OSN mailing list