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    Diagnostics ARP Table 504 Nginx Gateway Timeout

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

      @johnpoz Nope that's not it.

      Uninstalled 'arping', then deleted all MACs on both WANs, leaving only the standard 2 on each.

      My failover WAN is already back up to 127 again.
      My primary WAN is up to 1021. ๐Ÿ˜‘

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

        Nope, I'm not sure what could cause that either. Weird.

        I would check the system processes. See if you have anything running that is obviously and arp process.

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

          checking what processes are running would be good start for sure - but also you could just do process of elimination - how many packages exactly do you have installed? Nmap could do it for sure - but then that would have, or should have to be triggered.

          You could look to see if you have any crons scheduled.

          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 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.

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            • 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
                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

                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 2.8, 24.11

                      1 Reply Last reply Reply Quote 0
                      • 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 2.8, 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 2.8, 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 2.8, 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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