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New Member

DHCP relay over a point to point conenction

Hello everyone,

If I have a point to point connection No vlans) with the router on the far side having a FE ip address of 10.10.10.1 and configure DHCP relay on the far side router to point to a windows DHCP server on the near side of the point to point will the DHCP server see the request as coming from the 10.10.10.0 subnet and assign an IP address from that scope in the same way that it does for VLANS?

Thakns in advance. All replies rated

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Accepted Solutions
New Member

Re: DHCP relay over a point to point conenction

Hi,

On the 10.10.10.0 network, a PC will send a broadcast for DHCP address. By default, a router will not forward broadcasts, however a "ip helper-address" can be configured on the interface receiving the broadcast (10.10.10.1) to point it at the DHCP server.

It converts the broadcast to a unicast directed to the address configured (your DHCP server). The DHCP server sees it as coming from teh remote network and provided the server has connectivity to the remote network, and a scope configured for that network, it will assign an address from that scope.

Hope that helps,

Neil

1 REPLY
New Member

Re: DHCP relay over a point to point conenction

Hi,

On the 10.10.10.0 network, a PC will send a broadcast for DHCP address. By default, a router will not forward broadcasts, however a "ip helper-address" can be configured on the interface receiving the broadcast (10.10.10.1) to point it at the DHCP server.

It converts the broadcast to a unicast directed to the address configured (your DHCP server). The DHCP server sees it as coming from teh remote network and provided the server has connectivity to the remote network, and a scope configured for that network, it will assign an address from that scope.

Hope that helps,

Neil

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