DHCP Issue in Lab Environment

There are three computers running Server 2003 and three more running
XP in a lab at school. The clients and servers are paired up in
separate domains. Each server is running DHCP. The clients are just
as likely to get an IP address from a DHCP server on one of the other
domains as from "their" server. Is this normal and expected behavior
when everything is in the same broadcast domain?

Is there a way to filter DHCP offers (without segmenting the network)
so I only get an address from the server in my domain?

 

On 04/17/09 10:24, Bob wrote:
> There are three computers running Server 2003 and three more running
> XP in a lab at school. The clients and servers are paired up in
> separate domains. Each server is running DHCP. The clients are just
> as likely to get an IP address from a DHCP server on one of the other
> domains as from "their" server. Is this normal and expected behavior
> when everything is in the same broadcast domain?

Yes, this is what I would expect to happen. You have effectively set up
a race condition where the client will take the first reply that it
receives.

> Is there a way to filter DHCP offers (without segmenting the network)
> so I only get an address from the server in my domain?

Not that I'm aware of.

I'd look and see if it's possible to drain your DHCP pool so that there
are no IPs to offer for lease except for reserved addresses which are
tied to MACs. Thus the DHCP server would offer a lease to it's known
clients but no other clients.

If your clients don't need to talk to the other servers I suppose you
could do some sort of MAC based firewall so that only the proper server
would hear the DHCP request...



Grant. . . .

 

Hello Bob,

DHCP is first come, first serve principal. You can not define a DHCP server
for the client if they are on the same broadcast domain. So split the network
with routers to separate subnets.

Best regards

Meinolf Weber
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> There are three computers running Server 2003 and three more running
> XP in a lab at school. The clients and servers are paired up in
> separate domains. Each server is running DHCP. The clients are just
> as likely to get an IP address from a DHCP server on one of the other
> domains as from "their" server. Is this normal and expected behavior
> when everything is in the same broadcast domain?
>
> Is there a way to filter DHCP offers (without segmenting the network)
> so I only get an address from the server in my domain?
>