Pfsense and 2 Dynamic Public IP's - How to Configure?

Wonderful world of cable isp providers...

I have 2 dynamic IPs that I can attribute to domain names (dyndns) and server ports as I like BUT I can't figure out how to do it in Pfsense.

I currently have a 2 NIC lagg to my 24 port switch, and 2 NICs to my cable modem.

I have the WAN assigned as DHCP to pick up the first public IP address.

How do I pull the second dynamic IP with Pfsense?

All I can find so far is Virtual IP but this is configured for static IP's rather than dynamic so I don't see a place to poll the ISP's DHCP server for the IP.

I suppose I could grab both IP's by plugging the 2 ports from the modem into my server to see the 2 IP's and then spoof the MAC addresses from my server onto the Pfsense router and hope that my ISP preferentially serves me the same dynamic IP if I maintain the mac addresses but this seems like a bit of a crap shoot.

I assume plenty have gone before me on this one but I'm not having much luck googling an answer to this one.


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If you have two ports from the modem you could just get another NIC for pfsense and configure that as a second WAN interface to get both IPs. But I'm not really sure what advantage it would be to have two dynamic IP addresses on the same connection?

The advantage, as I see it, is the ability to host a couple of discrete domain names and then separate them into different vlans one for my lab_dungeon, and the other for work. I would go for 5 static IP's if they weren't so darn expensive. My cable company charges 3 times as much for a "business" account that has less bandwidth and they won't provide cheap static IP's to residential users.

Fair enough. I'm not sure if there is a better way of doing it but the only way I can think of is to have two wan NICs on your pfsense machine and connect them both to the modem. If the modem only has one port then just put a switch in between the modem and the two pfsense WAN ports.

If you have a managed switch you may be able to do it with one wan nic by using VLANs but I'm not sure if that would work or not.

I have 9 nics (2 - 4 port intel nics plus an onboard intel nic) on the pfsense box and the cable modem has 5 ports so nics aren't an issue. My HP procurve 1810G-24 does trunks and vlans quite well.

The bit I'm still missing is getting the IP from the DHCP on WAN2.

I would assume that you just have them both set to dhcp and connected to the modem and the ISP dhcp server will sort out the rest

I suspect that I will have to reboot the modem for things to sort themselves out. Will wait till swmbo is sleeping this evening and see if a reboot results in an IP.

Hunch confirmed... Rebooted the modem this evening and I now have access to both public IPs. One on WAN the other on WAN2.