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    Diagnostics ARP Table 504 Nginx Gateway Timeout

    Scheduled Pinned Locked Moved General pfSense Questions
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    • M
      manicmoose
      last edited by manicmoose

      I already checked for 'arp' processes and there's nothing over and above what 'arpwatch' is doing:

      /usr/local/sbin/arpwatch -z -Z -f /usr/local/arpwatch/arp_igb2.5.dat -i igb2.5
      /usr/local/sbin/arpwatch -z -Z -f /usr/local/arpwatch/arp_igb2.99.dat -i igb2.99
      /usr/local/sbin/arpwatch -z -Z -f /usr/local/arpwatch/arp_igb2.999.dat -i igb2.999
      /usr/local/sbin/arpwatch -z -Z -f /usr/local/arpwatch/arp_igb2.10.dat -i igb2.10
      /usr/local/sbin/arpwatch -z -Z -f /usr/local/arpwatch/arp_igb2.20.dat -i igb2.20
      /usr/local/sbin/arpwatch -z -Z -f /usr/local/arpwatch/arp_igb2.50.dat -i igb2.50
      

      My WANs are on diff. physical NICs, so different 'igb' numbers to this one - so presumably arpwatch is behaving itself.

      As for cron, it all appears kosher to me:

      1,31	0-5	*	*	*	root	/usr/bin/nice -n20 adjkerntz -a
      1	3	1	*	*	root	/usr/bin/nice -n20 /etc/rc.update_bogons.sh
      1	1	*	*	*	root	/usr/bin/nice -n20 /etc/rc.dyndns.update
      */60	*	*	*	*	root	/usr/bin/nice -n20 /usr/local/sbin/expiretable -v -t 3600 virusprot
      30	12	*	*	*	root	/usr/bin/nice -n20 /etc/rc.update_urltables
      1	0	*	*	*	root	/usr/bin/nice -n20 /etc/rc.update_pkg_metadata
      0,15,30,45	*	*	*	*	root	/etc/rc.filter_configure_sync
      0	11	4-10	*	*	root	/usr/local/bin/php /usr/local/www/pfblockerng/pfblockerng.php dcc >> /var/log/pfblockerng/extras.log 2>&1
      */1	*	*	*	*	root	/usr/sbin/newsyslog
      1	3	*	*	*	root	/etc/rc.periodic daily
      15	4	*	*	6	root	/etc/rc.periodic weekly
      30	5	1	*	*	root	/etc/rc.periodic monthly
      */1	*	*	*	*	root	/usr/local/pkg/servicewatchdog_cron.php
      */5	*	*	*	*	root	/usr/bin/nice -n20 /usr/local/bin/php -f /usr/local/pkg/snort/snort_check_cron_misc.inc
      */2	*	*	*	*	root	/usr/bin/nice -n20 /sbin/pfctl -q -t snort2c -T expire 900
      5	1,7,13,19	*	*	*	root	/usr/bin/nice -n20 /usr/local/bin/php -f /usr/local/pkg/snort/snort_check_for_rule_updates.php
      15	*	*	*	*	root	/usr/local/bin/php /usr/local/www/pfblockerng/pfblockerng.php cron >> /var/log/pfblockerng/pfblockerng.log 2>&1
      16	3	*	*	*	root	/usr/local/pkg/acme/acme_command.sh "renewall" | /usr/bin/logger -t ACME 2>&1
      

      "/etc/cron.d/at" only has 'atrun' in it.

      I do have nmap installed, but I've had that for as long as I remember without issues - and like you said - it does nothing unless triggered/called explicitely.

      Tried restarting 'arpwatch' and deleting all MAC entries but they soon returned.

      Uninstalled 'arpwatch' and nmap - no difference
      Had HAproxy installed (not currently being used) so uninstalled that. No change.
      Rebooted - no difference.

      The only 'arp' process I've seen pop up periodially is:

      /usr/sbin/arp --libxo json -an
      

      I'm not sure what they are related to.

      At this point I'm a bit stumped.

      1 Reply Last reply Reply Quote 0
      • M
        manicmoose
        last edited by

        Think I've "solved" it. ๐Ÿค”

        ntopng seems to be the culprit - I disabled it and all the ARPs have stopped. I haven't modified ntopng in ages, so maybe the config has become corrupted and it's doing something it's not supposed to be. Odd one.

        I'll wait awhile before re-enabling it, but I will delete the data/config and re-install it fresh to ensure it's happier than it was.

        Barring another re-occurance, thanks for the help folks!

        johnpozJ 1 Reply Last reply Reply Quote 0
        • 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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          Please don't Chat/PM me for help, unless mod related
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          M 1 Reply Last reply Reply Quote 0
          • 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 2.7.2, 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

                  L 1 Reply Last reply Reply Quote 0
                  • 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 2.7.2, 24.11

                      1 Reply Last reply Reply Quote 0
                      • 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 2.7.2, 24.11

                            L 1 Reply Last reply Reply Quote 0
                            • 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 2.7.2, 24.11

                                L 1 Reply Last reply Reply Quote 0
                                • 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 ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                                      L 1 Reply Last reply Reply Quote 0
                                      • 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?

                                        1 Reply Last reply Reply Quote 0
                                        • 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 2.7.2, 24.11

                                            L 1 Reply Last reply Reply Quote 0
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