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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 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

      M 1 Reply Last reply Reply Quote 0
      • 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˜‘

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            • 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

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                      • 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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                                    • 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?

                                          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

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