DHCP Relay Destination

cdall1979 · Jul 15, 2013, 2:37 PM

Is it possible to have pfSense act as a DHCP server and respond to relay requests? Meaning, can an upstream device relay DHCP requests to pfSense? I see that pfSense can act as a relay agent, but I would actually need the opposite.

doktornotor · Jul 15, 2013, 2:40 PM

Uhm? DHCP server will respond to any requests, relayed or not. No configuration required for this.

jimp · Jul 15, 2013, 4:16 PM

It may answer, though the server may not give out the IPs you want to a relayed request…

The ability to separate out pools for relayed setups isn't in our GUI, so for most relay setups it wouldn't make sense to use pfSense as the DHCP server.

cdall1979 · Jul 15, 2013, 6:57 PM

Correct, I actually just tried this, and it doesn't let me setup a pool since it falls outside the range of the "LAN" subnet which is a /30 off a router. The "Clients" would be sitting behind that upstream router and the router would relay DHCP requests to the pfSense. It seems this isn't doable?

jimp · Jul 15, 2013, 7:00 PM

Correct, it's not currently possible.

markn62 · Aug 16, 2013, 4:50 PM

Does PfSense need to recognize an Agent-ID identifier for DHCP relay to work?

twibowo · Oct 18, 2013, 6:36 AM

@cdall1979:

Correct, I actually just tried this, and it doesn't let me setup a pool since it falls outside the range of the "LAN" subnet which is a /30 off a router. The "Clients" would be sitting behind that upstream router and the router would relay DHCP requests to the pfSense. It seems this isn't doable?

Hi Guys,
I am newbie here, would like to understand better on the DHCP configuration.
So does it means that pfsense can only provide DHCP pools ip address for directly connected network?
Is there any configuration for pfsense to provide ip address to remote network?

Thank you! :)

CopSoft_MM · Oct 22, 2013, 4:42 PM

There is actually a hack permitting this. You just have to assign the right subnet on a down interface. If you don't have down interfaces easily availlable what you could do is create a vlan and down it with ifconfig during bootup.

markn62 · Oct 22, 2013, 5:03 PM

There are plans in the next release for DHCP server to support multiple subnets.
https://redmine.pfsense.org/issues/2774

twibowo · Oct 23, 2013, 7:42 AM

@CopSoft_MM:

There is actually a hack permitting this. You just have to assign the right subnet on a down interface. If you don't have down interfaces easily availlable what you could do is create a vlan and down it with ifconfig during bootup.

Hi Bro Copsoft_MM,
Do you have the steps for this ?
Is it working well?

@markn62:

There are plans in the next release for DHCP server to support multiple subnets.
https://redmine.pfsense.org/issues/2774

Thanks for your info :)

markn62 · Jan 2, 2014, 7:10 PM

Yes CopSoft it would be helpful a few more details. Are you saying a down interface would be needed for each additional DHCP pool desired? I have about 10 gateways setup on the LAN. If I need 10 down interfaces this may not be a feasible or practical hack in my case.