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    Diagnostics ARP Table 504 Nginx Gateway Timeout

    Scheduled Pinned Locked Moved General pfSense Questions
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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?

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            • 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.

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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

                              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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                                    • L
                                      lddj9090 @johnpoz
                                      last edited by

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

                                      mac that could not resolve

                                      Is it possible to see which ARP requests could not be resolved or have to be resolved external?

                                      And how to figure out if pfsense has a problem resolving devices in its mac table? As I think this has to be the case. Pfsense has direct attached network.

                                      It takes about 3-5 minutes to display the ARP -a command output via ssh. Also when I check the output, I just see IP/Macs form our network (different VLANs).

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

                                        @jimp
                                        What do you mean by "disable DNS for the page"?

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

                                          I am now on a holiday, will check on it when I am back. Thanks for the support so far.

                                          1 Reply Last reply Reply Quote 0
                                          • jimpJ
                                            jimp Rebel Alliance Developer Netgate @lddj9090
                                            last edited by

                                            @lddj9090 said in Diagnostics ARP Table 504 Nginx Gateway Timeout:

                                            @jimp
                                            What do you mean by "disable DNS for the page"?

                                            It will stop the page from using DNS to resolve hostnames. DNS resolution is almost certainly what is slowing it down.

                                            Instead you'll just get a list of the MAC addresses and IP addresses without the hostnames.

                                            Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

                                            Need help fast? Netgate Global Support!

                                            Do not Chat/PM for help!

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