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    CARP, two WANs, only one public IP in each WAN

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    • M
      mcury Rebel Alliance
      last edited by mcury

      b3ab8275-1acc-46b7-96ed-5295b783ec13-image.png

      Without a /29 in both WANs, I wonder what would happen with NTP, DNS, pfblocker updates, dpinger, firmware updates, package updates and etc with the Slave firewall.
      Connections would leave slave firewall using the VIP and then, the return traffic would hit the master causing asymmetric routing.

      Perhaps a workaround for this issue would be by using NAT, something like:
      outbound NAT, mode manual:
      127.0.0.0/8 don't use CARP, use interface address.

      This would make connections from the firewall itself to use their own IP address instead of the VIP.

      What do you think, it should work, right ?

      dead on arrival, nowhere to be found.

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      • V
        viragomann @mcury
        last edited by

        @mcury
        Only the ISP routers have a single WAN, but both pfSense boxes can have a unique WAN IP and additionally share the CARP VIP behind them.

        @mcury said in CARP, two WANs, only one public IP in each WAN:

        Perhaps a workaround for this issue would be by using NAT, something like:
        outbound NAT, mode manual:
        127.0.0.0/8 don't use CARP, use interface address.

        This is the normal configuration in a CARP setup. There is nothing different to your situation.

        The secondary can make upstream connections using its interface IP in the private subnet through the ISP router and will get responses back properly.

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        • M
          mcury Rebel Alliance @viragomann
          last edited by mcury

          @viragomann said in CARP, two WANs, only one public IP in each WAN:

          This is the normal configuration in a CARP setup. There is nothing different to your situation.

          oh, nice.

          @viragomann said in CARP, two WANs, only one public IP in each WAN:

          The secondary can make upstream connections using its interface IP in the private subnet through the ISP router and will get responses back properly.

          So, no need for the NAT I was thinking about, nice.

          Based on what you said, this setup would work perfectly, right ?
          Any other insights that I should be aware about ? Very helpful so far

          dead on arrival, nowhere to be found.

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          • V
            viragomann @mcury
            last edited by

            @mcury said in CARP, two WANs, only one public IP in each WAN:

            So, no need for the NAT I was thinking about, nice.

            The workaround if you only have one public WAN IP for two nodes is to route the secondary's upstream traffic over the masters LAN interface. But this is not necessary in your example, since they are connected to a private subnet with enough addresses behind router.

            Based on what you said, this setup would work perfectly, right ?

            I think, it should work.

            M 1 Reply Last reply Reply Quote 2
            • M
              mcury Rebel Alliance @viragomann
              last edited by

              @viragomann said in CARP, two WANs, only one public IP in each WAN:

              I think, it should work.

              Great, I'll set that up in the following days 👍 Thanks

              dead on arrival, nowhere to be found.

              S V 2 Replies Last reply Reply Quote 0
              • S
                SteveITS Galactic Empire @mcury
                last edited by

                @mcury we’ve set up a client like this but with one WAN. Comcast business provides NAT even on a “bridged” connection.

                Presumably both the public IPs would be shared/CARP.

                Pre-2.7.2/23.09: 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 restart, or more depending on packages and device speed.
                Upvote 👍 helpful posts!

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                • V
                  viragomann @mcury
                  last edited by

                  @mcury
                  One piint to add. The gateway monitoring IPs should be public, since the gateway IP is local and says nothing about the internet connection.
                  But I think, you"re aware of this.

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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    Yup there are (unsupported) workarounds for using only one public IP address. But you wouldn't need to use them here because you are not using public IPs on the pfSense WANs at all.

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                    • M
                      mcury Rebel Alliance @stephenw10
                      last edited by

                      thanks everyone for the replies, this will be my first HA setup with pfsense =)

                      dead on arrival, nowhere to be found.

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