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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

      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

      1 Reply Last reply Reply Quote 0
      • 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

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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 2.8, 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

                              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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                                        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
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