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    ISP failover for inbound nat

    Scheduled Pinned Locked Moved NAT
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    • W
      war
      last edited by

      hi guys,

      I have three(3) wan lines. ISP1 is my primary inbound nat for my public servers. Is there a way that I can failover to my ISP2 and ISP3 if ISP1 is down for inbound nat portforwarding.

      thank you very much.

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by

        You would have to have outside users connect to a dynamic DNS name and bind that dynamic DNS name to a gateway group so it is updated with the address of the other circuit when there is a failover event.

        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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        • W
          war
          last edited by

          Hi Derelict,

          Thank you for your reply. If I have my own DNS servers on my domain. How should I configure it?

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          • DerelictD
            Derelict LAYER 8 Netgate
            last edited by

            Kind of depends on how you want your DNS to flow, bro.

            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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            • W
              war
              last edited by

              I do currently have three(3) ISPs. ISP1 is currently live, my sample ip is 1.1.1.1/24. How can I configure inbound failover on pfsense to use ISP2 (2.2.2.2/24) and ISP3 (3.3.3.3/24) for my public servers? Or this thing is not possible with pfsense?

              thank you.

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              • DerelictD
                Derelict LAYER 8 Netgate
                last edited by Derelict

                This is not a "pfSense problem" it is a problem with how the internet works. You need a mechanism to tell your outside clients to connect to a different address based on the status of your local WAN circuits.

                To do this using pfSense you would:

                1. Tell your outside clients to connect to a dynamic DNS host name
                2. Create a gateway group for WAN1, WAN2, WAN3
                3. Create a dynamic DNS entry for the host name and bind it to the aforementioned gateway group.
                4. Have a cocktail. You earned it.

                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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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by johnpoz

                  How you do this in the real world where you OWN the IPs is advertise your netblocks out of your different isp with different metrics when your primary goes down that route would go away and they would come in via one of your other routes.

                  If you do now own the IPs then sure you could change the fqdn to point to a different IP. Many dns services will set this up for you were if IP x doesn't answer so assume down, then they change the fqdn to point to your failover IP with a very short ttl on the fqdn

                  example
                  https://dnsmadeeasy.com/services/dnsfailover/

                  An intelligent man is sometimes forced to be drunk to spend time with his fools
                  If you get confused: Listen to the Music Play
                  Please don't Chat/PM me for help, unless mod related
                  SG-4860 24.11 | Lab VMs 2.7.2, 24.11

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