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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 @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. ๐Ÿ‘Œ

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          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?

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              • 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

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                          • 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.

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                              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

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

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

                                        hindered

                                        Pfsense is DHCP for certain networks, not for all though. Also pfsense handles DNS request from our internal DNS server, so we can use DNS blocklists.

                                        Pfsense DNS Override has active settings for some domains. Could there be an issue?

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

                                          how long does it take to display your arp -a table?

                                          from a cmd line? Where @stephenw10 was saying there could be a delay in the table being displayed is lots and lots of IPs in the mac that could not resolve, or take a while to resolve via external dns because they were public, and would do a public PTR query for their names.

                                          If you have directly attached network to pfsense, so it has devices in its mac table - but the dns for these is somewhere downstream or upstream that pfsense has a problem resolving - then guess this could cause a delay in the output of your mac address table. Which could cause a timeout in the gui, etc.

                                          But with only a few hundred entries and local dns, etc.. I don't see how that could be a problem.. When from say ssh you do a arp -a for your arp table how fast does it display?

                                          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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                                          • jimpJ
                                            jimp Rebel Alliance Developer Netgate
                                            last edited by

                                            You could edit the source and disable DNS for the page. There should probably be an option on that page to disable it anyhow since it really does not scale well.

                                            diff --git a/src/usr/local/pfSense/include/www/diag_arp.inc b/src/usr/local/pfSense/include/www/diag_arp.inc
                                            index 568657f2ff..eed0b38eb2 100644
                                            --- a/src/usr/local/pfSense/include/www/diag_arp.inc
                                            +++ b/src/usr/local/pfSense/include/www/diag_arp.inc
                                            @@ -88,7 +88,7 @@ function prepare_ARP_table($json = false) {
                                                    // Resolve hostnames and replace Z_ with "".  The intention
                                                    // is to sort the list by hostnames, alpha and then the non
                                                    // resolvable addresses will appear last in the list.
                                            -       $dnsavailable=1;
                                            +       $dnsavailable=0;
                                                    $dns = trim(_getHostName("", "8.8.8.8"));
                                                    if ($dns == "") {
                                                            $dns = trim(_getHostName("", "8.8.4.4"));
                                            
                                            

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