DHCP

From: Jeigh (folkens.jason_at_acd.net)
Date: 09/17/04 

Date: Thu, 16 Sep 2004 23:54:56 -0400

I'm confused.

Heres my situation...

I have 1 DHCP Server with two scopes.
The dhcp server is 192.168.1.2.

The first scope handles 192.168.1.x
The second scope handles 192.168.2.x

The subnets are connected through a router that passes bootp through it....
In a seperate implementation, there may be a dhcp relay agent, but since
there are no significant configuration options set when installing a dhcp
relay agent, I don't think that changes the answer to this quesiton so lets
pretend that the router passes bootp traffic to the subnet with the DHCP
server.

How does the DHCP server determine which subnet a dhcp client is on, prior
to the server giving the client its new IP. In a routed network, where
there are multiple scopes, different dhcp options must be set up for each
individual scope, and each scope is used to set options for all dhcp clients
on a given subnet... but how does DHCP know which subnet a specific client
is coming from unless it already has an IP address?

I've read documentation stating that in a multihomed DHCP server setup, the
DHCP server actually needs to have a seperate nic to be associated with each
individual scope... but I cant believe that that is the case in this
situation because if that were true, then DHCP Relay agent would have a very
limited purpose, and bootp would never be routed.

any ideas?

-- Jason

Relevant Pages

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