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    ISP do not provide more then 1 public ip...

    Scheduled Pinned Locked Moved HA/CARP/VIPs
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    • K
      kira12
      last edited by

      Hello Guys,

      i want use CARP with 2x ISP but both are dont provide more then 1 public ip. I have a way to make it possible?

      best regards René

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      • N
        npiersma
        last edited by

        Hello René,

        If you want to use CARP you need 3 IP addresses in the same subnet/broadcast domain.

        One is your MASTER IP, one is your BACKUP IP and one is your shared IP. So you need a /29 as a minimum. ISP handing out /30 or spoofed /32 addresses won't really work.

        Please read vorkbaard's excellent walkthrough on setting up HA and CARP.

        You can set up failover with two ISP lines each with its own IP address. However, in case of a fail-over/failure, your internal clients will use a different outside IP address.

        Practical approach;
        Have your ISP modem hand-out private IP, setup CARP and have the modem forward all data (DMZ host) to your shared IP address. Poormans solution, but does work.

        Best would be to have two separate ISP internet connections (with separate physical cable paths) and have them delivered with a /30 subnet.

        Regards
        Niels

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        • DerelictD
          Derelict LAYER 8 Netgate
          last edited by

          Best would be to have two separate ISP internet connections (with separate physical cable paths) and have them delivered with a /30 subnet.

          I think you mean /29.

          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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          • N
            npiersma
            last edited by

            Correct
            /30 is only good for point to point.
            /29 makes live certainly more easier when carp is required.
            Niels

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            • K
              kira12
              last edited by

              Hello Niels,

              thanks for the help, i cant change my ISP. How can i forward my data to the private ip of the Modem?

              best regards René

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              • N
                npiersma
                last edited by

                René,

                Depends on your modem. You can. Ask your isp for the instructions. But to you can try to log on to the modem and look for DMZ host or forwarding host and have it send all the data to your internal private specific IP address.

                Niels

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