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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 @manicmoose
      last edited by johnpoz

      yeah for some reason your arping for the the whole range? That makes no sense..

      But yeah if you are arping for them - and you get an answer, then yeah they would be in your arp table..

      I have no idea what in pfsense would be doing that.. Mine sure isn't

      @stephenw10 do you know of something in pfsense that could do that, or a package maybe? Arpwatch enabled on the wan interface?? Would be a guess, but I thought it just listens for arps - doesn't actual arp for stuff on its own.

      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 @johnpoz
        last edited by manicmoose

        @johnpoz Yep, I've never seen it before either.

        Short of a reboot - is there some subsystem I could restart to try and 'reset' it's brain, or are there multiple involved making it difficult to tell which one(s) would need to be done?

        Like the OP, I'm on 2.5.1-release as well.

        Edit: I have arpwatch installed/enabled, but neither of the WANs is selected to be monitored.

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

          Lets see if @stephenw10 has some idea - off the top of my head I have no idea what would cause that.. But does for sure explain why so many entries.

          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 @johnpoz
            last edited by

            @johnpoz Sounds good.

            I just checked the arpwatch 'database' entries, and none of the MACs on the WANs are in there - only local ones.

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

              Yeah arpwatch shouldn't do it - but it was just off the cuff guess to something that "could" maybe do it..

              Drawing a blank - maybe after some more coffee something will come to me.. But atleast we have a piece of the puzzle to work with.. What would cause pfsense to arp for every IP in a range that is on the wan.. Not thinking of any packages you could add that could be setup to scan??

              The nmap package "could" do it for sure - but you would have to kick that off..

              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 @johnpoz
                last edited by

                @johnpoz Hmm....good point - I have 'arping' installed, and that could have been at the same time I added the 2nd WAN (can't really recall).

                Maybe it's the culprit as that's kind of what it's job is. I might uninstall it and see if that helps.

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

                  Yeah arping could prob do it too - but was not aware it had any sort of scanner option or that you could do it on a schedule sort of thing.. I currently don't have that installed.

                  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 @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).

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                                • 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?

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