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    Carp with single wan ip

    Scheduled Pinned Locked Moved HA/CARP/VIPs
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    • S
      sirex
      last edited by

      Since pfsense 2.2, i understand it's now possible to do CARP with only a single WAN IP.

      Is that just a case of using a /30 subnet of rfc1918 addresses on the WAN interface of each pfsense router, and setting the CARP virtual IP to be the one assigned from the ISP ? Then using the auto outbound NAT mode ?

      I've not had much luck on finding documentation on exactly how to do it, just lots on how to do it with multiple WAN IPs (which i don't have). Would greatly appreciate a blog post of something to point me in the right direction (hell, even an ascii diagram!).

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      • dotdashD
        dotdash
        last edited by

        Works with some caveats. This thread among others has notes- https://forum.pfsense.org/index.php?topic=87546.0

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        • S
          sirex
          last edited by

          aha. i searched for 'carp with one ip' not 'carp with 1 ip'. so close but no cigar !

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          • DerelictD
            Derelict LAYER 8 Netgate
            last edited by

            Any blog post or diagram should tell you to get a /29. That is how it is done. Anything worth HA is worth doing right, IMHO.

            And you cannot use Automatic outbound NAT with CARP/HA. It must be manual to the CARP VIP is used there.

            Chattanooga, Tennessee, USA
            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
            Do Not Chat For Help! NO_WAN_EGRESS(TM)

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