Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    1:1 NAT not working. Replacing Checkpoint with Pfsense

    Scheduled Pinned Locked Moved NAT
    19 Posts 3 Posters 2.0k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      OK so you want to 1:1 NAT from one of those to another address on a different subnet on the inside. Those are usually RFC1918 addresses, like 192.168.1.100.

      https://www.netgate.com/docs/pfsense/book/nat/1-1-nat.html

      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)

      1 Reply Last reply Reply Quote 0
      • S
        Su30MKI
        last edited by

        @Derelict The DMZ network is 128.50.0.0/16. Should I change it to class C IP address for the NAt to work?

        1 Reply Last reply Reply Quote 0
        • DerelictD
          Derelict LAYER 8 Netgate
          last edited by

          No, it doesn't matter, but those are not private addresses, they are assigned to the United States Department of Defense.

          https://en.wikipedia.org/wiki/Private_network

          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)

          1 Reply Last reply Reply Quote 0
          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

            Why in the world would of used 128.50?? Clearly those are NOT yours... And a /16 - so 65k some hosts?

            Just at a loss here. Yes you should fix it - you should use rfc1918 space - what its designed for.. And you should use an appropriate sized network.. If for no other reason you don't look like an idiot next time you have a question and post up your details..

            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 2.8, 24.11

            S 1 Reply Last reply Reply Quote 0
            • S
              Su30MKI @johnpoz
              last edited by

              @johnpoz It is still in my private network. How is that going to affect the NAT?

              1 Reply Last reply Reply Quote 0
              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                It is not private address space.. Its owned by the DOD..

                NetRange: 128.50.0.0 - 128.50.255.255
                CIDR: 128.50.0.0/16
                Organization: Department of Defense (DEPART)

                Sure you can technically use it - as long as you don't want any of those devices to talk to or get talked to by that network.. It just clearly points out to anyone that learns it that you don't understand even basic principles..

                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 2.8, 24.11

                S 1 Reply Last reply Reply Quote 1
                • S
                  Su30MKI @johnpoz
                  last edited by

                  @johnpoz Thank you for the reply. I will change it.

                  1 Reply Last reply Reply Quote 0
                  • S
                    Su30MKI
                    last edited by Su30MKI

                    Hello,

                    I got a break through. I changed the DMZ IP to 10.50.20.0/25. I NATted it to the DMZ server, Now I get connection refused error and not connection timed out error. I think the firewall is not letting the connection through.1_1535624624109_WAN-Rules.PNG 0_1535624624011_NAT-DMZ.PNG

                    1 Reply Last reply Reply Quote 0
                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      Why are you hiding your 10.50 address? /25 - so you go from a /16 to a /25... Ok Sure you didn't mess up something in the mask?

                      Firewall would not send a RST or anything if it was blocking it.. Unless you setup a specific REJECT rule.. So sounds more like your end box at 10.50.x.x you know that super secret rfc1918 address that nobody can know ;)

                      Simple sniff shows you if pfsense sends on the traffic to end device.

                      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 2.8, 24.11

                      1 Reply Last reply Reply Quote 0
                      • S
                        Su30MKI
                        last edited by Su30MKI

                        Alright, As you see the public ip is NATed to the DMZ server. Public IP : 125.21.XX.XX DMZ server IP : 10.50.20.3.
                        NAT 1:1 Mapping

                        Interface : WAN
                        External IP : 125.21.xx.xx
                        Internal IP : 10.50.20.3

                        WAN Rules

                        Protocol : IPV4
                        Source : 125.21.xx.xx
                        port : Any
                        Destination : Any.

                        Now the error is connection refused, Earlier it was connection timed out.

                        1 Reply Last reply Reply Quote 0
                        • DerelictD
                          Derelict LAYER 8 Netgate
                          last edited by

                          You are never going to have traffic into WAN sourced from an IP address on the WAN interface. The firewall rule should be sourced (presumably) from any which is any host on the internet.

                          The destination address should be the post-NAT real address of the destination server, or 10.50.masked.masked.

                          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)

                          1 Reply Last reply Reply Quote 0
                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by

                            You can for sure limit the source to your actual source out on the internet to get to this host your sending the nat too.. But if your putting in your actual wan IP, then as Derelict has stated - that is never going to work.

                            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 2.8, 24.11

                            1 Reply Last reply Reply Quote 0
                            • First post
                              Last post
                            Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.