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    Issue with Outbound NAT using Network and Broadcast addresses

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    • J
      jeanfpoulin
      last edited by

      We have a pfsense cluster that we use for our wireless clients. We use Manual Outbound NAT to translate the private IPs into public IPs. We are running issues where when we translate onto a subnet, it will use all of the addresses in that subnet including the network and broadcast addresses which shouldn't be valid.

      An example of this would be setting up the following NAT rule:
      Translate 10.21.1.0/24 to 66.64.12.0/27

      This NAT rule would then end up assigning some clients the ips 66.64.12.0 and 66.64.12.31 on the WAN side which should not happen since they are reserved for network and broadcast respectively.

      Any ideas?

      Thanks.

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by

        That is just doing what it has been told to do. It doesn't know they are network/broadcast addresses.

        If you were to specify only a /29 out of that for NAT you would expect it to use the first and last addresses.

        You can use a host alias range from and to the addresses you desire to use. Define the alias like 192.168.1.1-192.168.1.30 and the heavy lifting will be done for you.

        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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        • J
          jeanfpoulin
          last edited by

          Thank you Derelict. The Host Alias feature is doing exactly what I need and want it to. Guess I had missed it when reading through the documentation.

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