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    SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port

    Scheduled Pinned Locked Moved General pfSense Questions
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    • johnpozJ Offline
      johnpoz LAYER 8 Global Moderator @Guest
      last edited by

      @JohnUtiu said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

      MAC Address: Globalsc_XXXXXXX

      What is this mac address of, you say the 15 address changes - but is the mac staying the same?

      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 25.07.1 | Lab VMs 2.8.1, 25.07.1

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      • stephenw10S Offline
        stephenw10 Netgate Administrator
        last edited by

        The Globalscale MAC will be the 1100. They are the board manufacturer.

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        • johnpozJ Offline
          johnpoz LAYER 8 Global Moderator @stephenw10
          last edited by

          @stephenw10 yeah but he says his 15.x address is changing - quite possible this is wan IP?

          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 25.07.1 | Lab VMs 2.8.1, 25.07.1

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          • stephenw10S Offline
            stephenw10 Netgate Administrator
            last edited by

            Yup could be

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            • ? Offline
              A Former User @johnpoz
              last edited by

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              • dennypageD Offline
                dennypage
                last edited by

                This could simply be a bug in ntopng’s active discovery code. Compared to the main ntopng code, it’s rather immature and little used. I do not recommend it.

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                • stephenw10S Offline
                  stephenw10 Netgate Administrator
                  last edited by

                  Do you have any custom outbound NAT rules on OPT?

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                    A Former User @dennypage
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                      A Former User @stephenw10
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                        • dennypageD Offline
                          dennypage @Guest
                          last edited by

                          @JohnUtiu said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

                          Do you have any ideas about how a bug could result in a strange public ip addresses being sticked on the ip address of the interface?

                          The last two ntopng core dumps that were brought to my attention were memory corruption resulting from the use of active network discovery.

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                          • patient0P Online
                            patient0 @Guest
                            last edited by

                            @JohnUtiu said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

                            WAN tcp 192.xxx.xxx.xxx:51949 -> 15.179.xxx.xxx:22 SYN_SENT:CLOSED 2 / 0 120 B / 0 B
                            WAN tcp 192.xxx.xxx.xxx:62155 -> 15.179.xxx.xxx:80 SYN_SENT:CLOSED 2 / 0 120 B / 0 B

                            According to ipinfo.io and the RIPE db the IP range 15.179.0.0 to 15.188.255.255 is part of Amazon Technologies Inc..

                            You got an Amazon device that calls home?

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                            • johnpozJ Offline
                              johnpoz LAYER 8 Global Moderator @Guest
                              last edited by

                              @JohnUtiu said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

                              WAN tcp 192.xxx.xxx.xxx:51949 -> 15.179.xxx.xxx:22 SYN_SENT:CLOSED 2 / 0 120 B / 0 B

                              If that is not your address, why are you hiding it? Like me hiding that making a connection to 8.8.x.x ???

                              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 25.07.1 | Lab VMs 2.8.1, 25.07.1

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                              • dennypageD Offline
                                dennypage @patient0
                                last edited by

                                @patient0 said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

                                According to ipinfo.io and the RIPE db the IP range 15.179.0.0 to 15.188.255.255 is part of Amazon Technologies Inc..

                                You got an Amazon device that calls home?

                                More likely it's ntopng itself.

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                                • dennypageD Offline
                                  dennypage @Guest
                                  last edited by

                                  @JohnUtiu said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

                                  It seems that every time I run network discovery on ntopng, a connection is being opened FROM my WAN interface TO exactly the same 15.xxx ip address that is being sticked on the OPT interface.

                                  WAN tcp 192.xxx.xxx.xxx:51949 -> 15.179.xxx.xxx:22 SYN_SENT:CLOSED 2 / 0 120 B / 0 B
                                  WAN tcp 192.xxx.xxx.xxx:62155 -> 15.179.xxx.xxx:80 SYN_SENT:CLOSED 2 / 0 120 B / 0 B

                                  It's trying to connect to port 20 and 80 on this address.

                                  Where are you geographically?

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                                  • johnpozJ Offline
                                    johnpoz LAYER 8 Global Moderator @dennypage
                                    last edited by

                                    @dennypage said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

                                    More likely it's ntopng itself.

                                    Yeah and if some public internet IP wasn't obfuscated we could prob look up its PTR and glean some insight to what is is..

                                    You want help identifying what some odd public IP is, which you know isn't your actual IP, or the IP of your gateway from your isp - why are you hiding it.. Why are you hiding your rfc1918 IP as well?

                                    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 25.07.1 | Lab VMs 2.8.1, 25.07.1

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                                    • dennypageD Offline
                                      dennypage @Guest
                                      last edited by

                                      @JohnUtiu said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

                                      WAN tcp 192.xxx.xxx.xxx:51949 -> 15.179.xxx.xxx:22 SYN_SENT:CLOSED 2 / 0 120 B / 0 B
                                      WAN tcp 192.xxx.xxx.xxx:62155 -> 15.179.xxx.xxx:80 SYN_SENT:CLOSED 2 / 0 120 B / 0 B

                                      It's trying to connect to port 20 and 80 on this address.

                                      Btw, assume that you meant port 22 rather than port 20. This is ssh.

                                      Some of the (really bad) things ntopng does when active discovery is enabled is to run ssh, snmp and http probes against hosts it finds in the network.

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                                        A Former User @dennypage
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                                          A Former User @patient0
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                                          • S Offline
                                            SteveITS Galactic Empire @Guest
                                            last edited by

                                            @JohnUtiu said in SG-1100 - Ntopng Network Discovery finds strange 15.xxx addresses on disconnected OPT port:

                                            ntopng ... on a Netgate 1100

                                            FYI Netgate marks that package as "requires SSD" due to the usually high I/O generated:
                                            https://www.netgate.com/supported-pfsense-plus-packages

                                            You might check https://docs.netgate.com/pfsense/en/latest/troubleshooting/disk-lifetime.html.

                                            Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                                            When upgrading, allow 10-15 minutes to reboot, or more depending on packages, CPU, and/or disk speed.
                                            Upvote 👍 helpful posts!

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