DHCP multiple interfaces



  • I've been running the DHCP server on my primary LAN fine for months. I have another LAN network which pfsense is now connected to, and I was trying to configure PFsense to act as the DHCP server on that LAN as well. I checked "Enable DHCP server on LAN2 interface" and set the IP range. I allowed all traffic on that interface. I verified with a packet capture that PFsense receives the DHCP request. It does not send a reply, though. Any ideas?



  • I figured it out. My fault. I wasn't releasing the DHCP lease from the old DHCP server before I sent the DHCP request. It was actually working fine all along.


  • Rebel Alliance Developer Netgate

    Release/Renew gets a little odd on Windows, especially if you are changing subnets. I find the best way is to physically unplug the line for about 10 seconds (slow count, x-<one thousand="">) and then plug it in the other network.</one>



  • I didn't even change subnets. I used a different range on the same subnet. Either DHCP servers ignore requests from source IP's which it didn't lease, or it ignores source IP's which aren't within the range it will lease. My old DHCP server (Windows) did the same. You have to release any leases from other servers before a new DHCP server will respond.

    I always assumed XP's "repair network connection" did a release and renew. Apparently not, probably so network connectivity isn't disrupted.


  • Rebel Alliance Developer Netgate

    XP's repair option does renew the IP address, but I'm not sure it does a release first.

    Vista/7 go even farther in their 'Diagnose' option, they disable/enable the whole adapter as part of the routine.


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