Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I am trying to figure out how I can have a machine on the "LAN" nic of pfSense get a DHCP address from a DHCP server on the "WAN" nic of pfSense (happens to be a Windows Server 2003 machine if that matters).

I tried turning off the pfSense DHCP and turning on the "Enable DHCP relay on lan interface" and using either the 'proxy requests to dhcp server on wan subnet' or typing in the ip address of the dhcp server ( The client machines just time out trying to reach a dhcp server (tried on win xp and win 7).

I thought maybe the issue is the ip subnet, so I tried changing the LAN ip address to a address, but then for some reason it does not work at all - I can not access the pfSense web admin when setting my machine to a static for example. I checked that .19 and .4 are not being used on the WAN or LAN.


I have a simple install of pfSense, two nic cards. All the settings are default from the install and I did not block anything, meaning my firewall settings screen shows no filters. No VLANs, no routes, etc.

My "WAN" nic is set to use dhcp to get it's address ( My "LAN" nic is set to a static "" address.

If I have DHCP turned on for the LAN interface and plug a machine in to the LAN side, it works great - I get a 192.168.1.x address on the machine and I can communicate through to the WAN.

I can not figure out how to have pfSense pass the dhcp request through to the WAN port and get an ip address that way (within the 172.16.1.x range)?


Do I have to define a firewall rule on the wan interface to allow dhcp or ? in? in order for the dhcp relay to work?

share|improve this question
why do you need to assign IP's from wan's dhcp, why not make use of routes to allow you to access those IP's easily through pfsense? –  anthonysomerset May 10 '11 at 19:18
did you disable dhcp server on both interfaces, as it is written in the docs ? –  Wacek May 10 '11 at 19:26
Yes, DHCP disabled on both. For routes, would I have to define a route for each machine - if so that would be an issue / maintenance headache. –  Scott Szretter May 16 '11 at 16:02

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.