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    Mixed IPv4 / IPv6 and Multi WAN

    Scheduled Pinned Locked Moved Routing and Multi WAN
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    • T Offline
      tman222
      last edited by

      Hi all,

      What would be best way to setup a multiple WANs with failover on pfSense if the first connection only supports IPv4 and the second connection supports both IPv4 and IPv6, with the caveat being that IPv4 on that second connection is limited by CGNAT? I understand IPv4 and IPv6 can't be mixed in the same gateway group so 2 groups would have to be created. However, how does the failover work then? Assuming I wanted to traffic to flow over IPv4 (primary connection) and then when that connection goes down fail over to the secondary (which is IPv6), how could one set this up? Thanks in advance.

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      • S Offline
        SteveITS Rebel Alliance @tman222
        last edited by

        @tman222 I’d expect your IPv4 rules would have a gateway group and v6 would have just the WAN2 gateway. Unless you want you block v6 if using WAN1?

        Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
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          tman222 @SteveITS
          last edited by

          @SteveITS said in Mixed IPv4 / IPv6 and Multi WAN:

          @tman222 I’d expect your IPv4 rules would have a gateway group and v6 would have just the WAN2 gateway. Unless you want you block v6 if using WAN1?

          Hi @SteveITS - thanks for the response. Yes, I would actually like to use the IPv4 based connection exclusively and then only switch to the IPv6 based connection when the IPv4 connection goes down. How would one set this up on pfSense? I imagine one the challenges might be if devices get assigned both an IPv4 and IPv6 address from the start as they could end up preferring to use IPv6 over IPv4. Thanks again.

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            SteveITS Rebel Alliance @tman222
            last edited by

            @tman222 Yeah I don’t know that is possible. With IPv4 NAT the PCs have one IP. With IPv6 they’d need one from each interface. So maybe https://docs.netgate.com/pfsense/en/latest/network/ipv6/nat.html but then the device would need to not use it since it wouldn’t work normally. And generally it’s the preferred protocol.

            Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
            When upgrading, allow 10-15 minutes to reboot, or more depending on packages, and device or disk speed.
            Upvote 👍 helpful posts!

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