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    Frequent disconnection when with WAN network when using static IP from ISP

    Scheduled Pinned Locked Moved General pfSense Questions
    static ipwan gateway
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    • R
      rajnetgen @stephenw10
      last edited by

      @stephenw10 have checked the ARP table for changes when there is gateway down issues.
      I did saw that the when the gateway starts to show pack loss and goes down there is a time left under status for the gateway IP in ARP table.
      FTTH 122.17.13.1 74:22:dd:01:51:4a broadband.com Expires in 43 seconds ethernet
      FTTH 122.17.13.145 94:e1:bd:13:c6:20 broadband.com Permanent ethernet

      If I delete the entry then the gateway starts to instantly recover and come back online.
      Else I guess it will wait for the time to expire and then come back online.

      But this does not happen everytime and this time rune for 1200 seconds and sometimes it goes to zero and then again start from 1200 seconds

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

        You should still set the monitoring IP to something external. The ISPs gateway is under no obligation to respond to ping. It may just drop ping requests when it's loaded.

        R N 2 Replies Last reply Reply Quote 0
        • R
          rajnetgen @stephenw10
          last edited by

          @stephenw10
          Yes I use 3rd party like google dns or cloudflare as default but had changed to gateway to test
          The behaviour is same for both cases.
          When the connection starts to get packet loss, if I go to ARP table and delete the gateway entry then it starts to come back online else it wait for timeout and then come back online automatically.

          Can we reduce the ARP timeout?

          stephenw10S 1 Reply Last reply Reply Quote 0
          • N
            nischay @stephenw10
            last edited by

            @stephenw10

            I tried both 1.1.1.1/8.8.8.8 even tried ip of my public VM running in digital ocean in Bengaluru, India as GW monitoring IP.

            I configured same static IP in my OpenWRT box and strangley not seeing any issue runnning fine for more then 2 weeks without any downtime.

            For now I have configured port forwarding to pfsense and added OpenWRT LAN ip as gateway in Pfsense.

            1 Reply Last reply Reply Quote 0
            • JonathanLeeJ
              JonathanLee
              last edited by

              Have you checked your category 5, 6 or 7 the rj45 cable with a cable tester?

              Make sure to upvote

              N 1 Reply Last reply Reply Quote 0
              • N
                nischay @JonathanLee
                last edited by

                @JonathanLee

                It is CAT6 5 Feet patch cable. Used same cable to connect OpenWRT to ISP ONT.

                JonathanLeeJ 1 Reply Last reply Reply Quote 0
                • JonathanLeeJ
                  JonathanLee @nischay
                  last edited by JonathanLee

                  @nischay they have speed ratings for each type and use. is it a shielded one? It could be getting interference from elevators, or florescent lights, many issues. Swap out that cable for an upgraded one

                  Make sure to upvote

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

                    @rajnetgen said in Frequent disconnection when with WAN network when using static IP from ISP:

                    Can we reduce the ARP timeout?

                    Yes you can set it as a system tunable: net.link.ether.inet.max_age
                    pfSense/FreeBSD uses 1200s by default.

                    N 1 Reply Last reply Reply Quote 1
                    • N
                      nischay @stephenw10
                      last edited by

                      @stephenw10

                      Thanks for pointing it out. I have updated net.link.ether.inet.max_age to 60 seconds same as Linux default. I will update here if it help to resolve issue.

                      [root@pfsense-fw ~]# sysctl net.link.ether.inet.max_age
                      net.link.ether.inet.max_age: 60
                      
                      1 Reply Last reply Reply Quote 2
                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        I've once seen an ISP that would fail to arp for devices in that situation and so required a lower value there. So it's unlikely, but possible.

                        N 1 Reply Last reply Reply Quote 1
                        • N
                          nischay @stephenw10
                          last edited by nischay

                          @stephenw10

                          Seems like changing ARP Cache TTL to 60 seconds fixed issue I was observing. Finally I have resolution to my issue such a relief. 😌

                          1 Reply Last reply Reply Quote 2
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