Does two pfsense + CARP necessarily require two WAN IP?
I am looking to setup CARP following this guide across two pfSense firewalls.
I have setup CARP before on a WAN link with a big IP space, so allocating a distinct WAN IP per each device (as shown in the guide) was palatable.
Now, I am trying to do the same, but only one WAN IP is available per link.
Is there a way to use only one WAN IP?
Edit: What if you have the following configuration? (would this work?)
- WAN1: WAN IP 1.2.3.4, local IP 192.168.10.1
- WAN2: WAN IP 1.2.3.5, local IP 192.168.20.1
- pf1: On interface WAN1, local IP 192.168.10.10; on WAN 2, local IP 192.168.20.10;
- pf2: On interface WAN1, local IP 192.168.10.11; on WAN 2, local IP 192.168.20.11;
- On both pf1 and pf2, monitor IP set to the ISP-appropriate value
- VIP on 192.168.10.100, 192.168.20.100
No, carp requires three WAN IPs.
It does not, it depends on your Setup. I have a working solution with 1 IP. The Slave just uses the Master as a gateway.
CARP is like VRRP, HSRP and most other routing redundancy protocols, you must have 3 static IPs in the same subnet.
That may change at some point in the future, but it's true for the time being.