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    Multiple ISP routers with the same IP address

    Scheduled Pinned Locked Moved Routing and Multi WAN
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    • H
      horace
      last edited by

      Hello everyone!
      I need to load balance an office with multiple connections.
      The problem is that I have 3 routers and they have hardcoded the same IP address and I cannot be changed (we called the ISP with no luck).

      My situation is
      ISP 1: 192.168.15.1/24
      ISP 2: 192.168.15.1/24
      ISP 3: 192.168.15.1/24
      and my pfsense box.

      Is there a way with pfsense to do multiple wan with this scenario? I don't mind using tons of VLAN, VIP or something else.

      Thanks!

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by

        @horace:

        The problem is that I have 3 routers and they have hardcoded the same IP address and I cannot be changed (we called the ISP with no luck).

        Get another ISP.

        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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        • C
          chris4916
          last edited by

          multiple ISP routers from same ISP or mutilpe ISPs?

          Anyway, if protocols you intend to use support double NAT, you could easily attach one device behind here router that you NAT your hard-coded address into something unique. Then attach these devices to pfSense and define the addresses as gateway pointing to each ISP.

          ISP1 => router => 192.168.1.1 => router => 192.168.2.1
          ISP1 => router => 192.168.1.1 => router => 192.168.2.2
          ISP1 => router => 192.168.1.1 => router => 192.168.2.3

          attach pfSense WAN at 192.168.2.4 (all IPs are examples only) and your done, at the cost of double NAT.

          Jah Olela Wembo: Les mots se muent en maux quand ils indisposent, agressent ou blessent.

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          • H
            horace
            last edited by

            I can't change ISP now and I don't have any other router. I have only 3 ISP routers (from the same provider) and my pfsense box

            ISP router 1 with IP 192.168.15.1 <–> | -------------- |
            ISP router 2 with IP 192.168.15.1 <--> | pfsense box  |
            ISP router 3 with IP 192.168.15.1 <--> | -------------- |

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            • C
              chris4916
              last edited by

              So you're stuck with one single gateway isn't it?

              Jah Olela Wembo: Les mots se muent en maux quand ils indisposent, agressent ou blessent.

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              • H
                heper
                last edited by

                cant be done. you are gonna have to change isp's or add a double NAT mess.

                are you sure you can't modify the routers or do pppoe ?

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                • D
                  doktornotor Banned
                  last edited by

                  I think it's pretty obvious this absolutely CANNOT work, pfSense or not, without doing another layer of NAT in between. Not exactly sure what's still being discussed here? You cannot have 3 boxes with the same IP and expect to the router to be able to distinguish among them.  ::)

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                  • DerelictD
                    Derelict LAYER 8 Netgate
                    last edited by

                    @heper:

                    cant be done. you are gonna have to change isp's or add a double NAT mess.

                    Or convince the ISP they're being donkeys.

                    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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                    • R
                      ruio
                      last edited by

                      @doktornotor:

                      I think it's pretty obvious this absolutely CANNOT work, pfSense or not, without doing another layer of NAT in between. Not exactly sure what's still being discussed here? You cannot have 3 boxes with the same IP and expect to the router to be able to distinguish among them.  ::)

                      Someone pointed me out can you do that with RouterOS with something like this

                      add destination=0.0.0.0/0 gateway=192.168.1.1%ether1 routing-mark=Adsl1
                      add destination=0.0.0.0/0 gateway=192.168.1.1%ether2 routing-mark=Adsl2

                      This is why I was asking.

                      Btw I solved using a super ugly double NAT with multiple routers until we change ISP.

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