How to avoid multiple DHCP request forward to all Servers?

Simon Hobson dhcp1 at
Thu Apr 6 15:04:54 UTC 2017

Niall O'Reilly <niall.oreilly at> wrote:

> I believe that this approach will simply maximize the burden of future
> maintenance.
> I would recommend instead that you simply accept that the relay is operating
> correctly and focus instead on configuring your servers so that they offer
> only the addresses you require to clients on the different networks.


If the OP really wants requests from client1 to go to server 1, and requests from client 2 to go to server 2, then he either needs to introduce some sort of filtering in the relay agent (probably not supported), or run two relay agents (probably not supported on the router).
So if instead of running a relay agent on the router (it doesn't have to be in a router), he could run a relay agent in each network, configured to only send requests to the one server. But as you say, this seems designed to create more work than is required.

A simple way of having each server only answer "it's clients" would be to simply have a config where the subnet for 'the other clients" is empty. Ie, on server 1 :

subnet ... {
  range 192.168.1.xx 192.168.1.yy ;
subnet ... {};

And vice-versa on server 2.

That way, server 1 will just "do nothing" with clients in network 2, and server 2 will ignore clients from network 1.

Perhaps the OP could expand on why he feels the need for this, there may be a simpler way of doing what he wants.

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