DHCP Relay (Server) support?



  • Hi there,

    I am just about to redesign my companies office network which has been using pfSense for nearly 2 years now. I will continue to use it as well but need to bring a layer 3 switch into the mix due to some inter-vlan routing capacity expansion that is required.

    The switch in question is a Cisco 6509 with SUP720 3B supervisor modules installed. I am a Cisco guy and was planning to use Cisco's IP helper function in order to relay DHCP requests from the 7 VLAN's to my DHCP server. However I cannot seem to find anything to say that I can create multiple DHCP pools for subnets that don't exist on pfSense itself, nor can I find out if it supports receiving relays.

    Can anyone answer the above?

    And if pfSense doesn't then I will just use a DHCP server implementation on a VM, however I think this is a feature pfSense should support!

    Thanks


  • Banned

    Relay is fine. DHCP Server for "external" subnets => not done.



  • @doktornotor:

    Relay is fine. DHCP Server for "external" subnets => not done.

    Thanks for letting me know!

    Since this is the case, what is the point in pfSense being able to respond to relays then if it can only function as a DHCP to visible subnets?


  • Banned

    Well, the point it to forward DHCP to the DHCP server… Not sure what else do you mean?



  • @doktornotor:

    Well, the point it to forward DHCP to the DHCP server… Not sure what else do you mean?

    Don't worry I understand. You mean pfSense can be used as the relay, just not a relay end point.


  • Banned

    Well, "relay end point" and DHCP server sounds like the same thing to me :)



  • pfSense has a DHCP Relay service as well as a DHCP Server service. Either way, you're covered.



  • @KOM:

    pfSense has a DHCP Relay service as well as a DHCP Server service. Either way, you're covered.

    I don't think you guys understand what I am trying to say.

    I wanted to know if pfSense could be used to receive DHCP requests via a Cisco IP Helper relay service in order to provide DHCP for subnets that it has no local visibility of…

    However since I now know that pfSense does not support DHCP scopes outside of local interface subnets, obviously I cannot continue to use pfSense DHCP server after migrating to L3 switching for inter-vlan routing.

    Not a problem, I just wanted to know if I could continue to do so.... Oh well the Cisco SUP720-3B in the 6509 can do DHCP, otherwise its openDHCP server or something in a VM.

    Tom


  • Banned

    No, you cannot use pfSense to supply DHCP outside of the subnets configured on the firewall itself. It can relay them elsewhere. No idea what's your "relay endpoint".



  • @doktornotor:

    No, you cannot use pfSense to supply DHCP outside of the subnets configured on the firewall itself. It can relay them elsewhere. No idea what's your "relay endpoint".

    When I said relay endpoint I meant DHCP server that can serve scopes outside of its locally visible subnets. As in, the 'endpoint' of the DHCP request after its been relayed.