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    Diagnostics ARP Table 504 Nginx Gateway Timeout

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

      @manicmoose said in Diagnostics ARP Table 504 Nginx Gateway Timeout:

      ntopng seems to be the culprit

      While I don't profess to being a ntop guru by any means.. I don't get why it would be arping like that. I get what your saying that it stopped what your seeing - but not sure why it do that.. Ntop out of the box sure shouldn't be arping every IP for networks its attached too..

      An intelligent man is sometimes forced to be drunk to spend time with his fools
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      • M
        manicmoose @johnpoz
        last edited by

        @johnpoz Agreed - and it never used to, which is why I think it's become a little confused...

        Time to reset its brain when I re-enable it (later).

        1 Reply Last reply Reply Quote 0
        • stephenw10S
          stephenw10 Netgate Administrator
          last edited by

          It will it you have enabled this:

          Active Network Discovery
          
          Toggle the periodic discovery of network devices using multiple techniques that include ARP scan, MDNS and SSDP.
          

          That's not enabled by default.

          johnpozJ 1 Reply Last reply Reply Quote 0
          • johnpozJ
            johnpoz LAYER 8 Global Moderator @stephenw10
            last edited by

            Nor should it be enabled on your wan interface ;)

            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

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            • M
              manicmoose
              last edited by

              Yep, I get all that.

              As mentioned, I hadn't altered the ntopng config for ages, so I don't think that was it - but I've blown away the config now so I can't check.

              Nevertheless, it's solved so that's all I care about. 👌

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              • L
                lddj9090 @manicmoose
                last edited by

                @manicmoose
                Thanks for the information, unfortunately wasn't able to check in for a week.

                I have uninstalled ntopng, but still got a long waiting time to see the ARP entries. Will do a tcpdump to check further.

                johnpozJ L 2 Replies Last reply Reply Quote 0
                • johnpozJ
                  johnpoz LAYER 8 Global Moderator @lddj9090
                  last edited by

                  did flush the cache? The items would still be there for 20 minutes even if you uninstall what was arping for them.

                  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

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                  • L
                    lddj9090 @lddj9090
                    last edited by

                    @lddj9090
                    How can i clear the arp cache on pfsesne, all at once?

                    1 Reply Last reply Reply Quote 0
                    • L
                      lddj9090 @johnpoz
                      last edited by

                      @johnpoz

                      2-5 minutes.

                      johnpozJ 1 Reply Last reply Reply Quote 0
                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator @lddj9090
                        last edited by

                        arp -d -a

                        or from the gui click the clear arp table.

                        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

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                        • L
                          lddj9090 @johnpoz
                          last edited by

                          @johnpoz

                          Cleared the cache and tried again, still spinning for ages and timeout. Could "snort" be somehow involved?

                          johnpozJ 1 Reply Last reply Reply Quote 0
                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator @lddj9090
                            last edited by

                            You need to figure out why your wan has anything it.. Have gone over why there should be nothing in your wan network in your arp cache other than your gateway..

                            NOTHING should just be arping for every IP on a network.. especially our wan.. So there is something you set to arp, or some other reason.

                            You need to sniff on your wan and figure out what - are you arping, is it gratuitous arps? etc..

                            Out of the box pfsense with any package installed shouldn't be arping neither your wan network your lan side networks.. It would have to be some setting you did.. Like the ntop setting for network discovery.

                            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

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                            • L
                              lddj9090 @johnpoz
                              last edited by

                              @johnpoz
                              Alright, I will investigate further and talk back to you later. Thanks for the support so far!

                              stephenw10S 1 Reply Last reply Reply Quote 0
                              • stephenw10S
                                stephenw10 Netgate Administrator @lddj9090
                                last edited by

                                @lddj9090 Do you actually have WAN side ARP entries with public IPs?

                                Are they eventually being resolved by reverse DNS?

                                Could a completely different problem than @manicmoose had.

                                Steve

                                L 1 Reply Last reply Reply Quote 0
                                • jimpJ
                                  jimp Rebel Alliance Developer Netgate
                                  last edited by

                                  Last time someone was seeing ARP for random hosts on WAN it was from having their subnet mask on the WAN interface set to something ridiculous like 0 instead of what it should have been (e.g. 24, 29, etc.)

                                  If your WAN is set to a static address, double check your IP address and subnet mask settings.

                                  Whatever is upstream may be answering ARP for anything with its own MAC. That's unusual but not unheard of.

                                  Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

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                                  • L
                                    lddj9090 @stephenw10
                                    last edited by

                                    @stephenw10

                                    As far as I am aware, there aren't any public IP in my ARP output.

                                    Here is a snippet of the ARP -a output: arp_snippet_pfsense.txt

                                    We do have high availability sync enabled. As well as a bunch of Virtual IPs (CARP). Even though they all seem to be configured correctly, could that cause something unexpected?

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                                    • L
                                      lddj9090 @jimp
                                      last edited by

                                      @jimp

                                      I double-checked the WAN Interfaces static address settings, they are all setup correctly.

                                      2c157b07-369d-4874-b3d5-8248069b797f-image.png

                                      johnpozJ 1 Reply Last reply Reply Quote 1
                                      • johnpozJ
                                        johnpoz LAYER 8 Global Moderator @lddj9090
                                        last edited by

                                        And how many entries in your arp table? 1000's ??

                                        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

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                                        • L
                                          lddj9090 @johnpoz
                                          last edited by

                                          @johnpoz
                                          254

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                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator @lddj9090
                                            last edited by

                                            Then I doubt your problem is related to what the other poster was seeing in slow downs do to trying to resolve public IP names.

                                            Is pfsense not dhcp or dns for this network - where resolving names could be hindered, for ptr?

                                            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

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