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    DNS Stops working

    Scheduled Pinned Locked Moved DHCP and DNS
    36 Posts 5 Posters 3.5k Views
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    • GertjanG
      Gertjan
      last edited by

      Your doing some DNS related things with your firewall rules on LAN - all have a destination port of '53'.

      DNS uses UDP and can use TCP.

      Your not blocking ICMP - the protocol ping is using - so it will pass using the last, pass all rule for IPv4 stuff.
      ICMP does not use the concept of 'ports'.

      Ping to 1.1.1.1 should be possible from your LAN.

      Thse are my LAN rule :

      3838328e-62bf-4e23-975b-1981b3800fc5-image.png

      which is 100 % identical to your rules - I'm not blocking any DNS things. Just a big pass all.
      And I also use IPv6 .... (not related to your question).

      I can ping 1.1.1.1 just fine.

      No "help me" PM's please. Use the forum, the community will thank you.
      Edit : and where are the logs ??

      manjotscM 1 Reply Last reply Reply Quote 0
      • manjotscM
        manjotsc @Gertjan
        last edited by manjotsc

        @Gertjan When DNS is working I am able ping 1.1.1.1, but not when DNS stops. It's been months I trying figure this out and I dont have any dns rule on guest, still causes problem.
        thanks,

        Annotation 2020-06-16 045618.png

        Vendor: HP
        Version: P01 Ver. 02.50
        Release Date: Wed Jul 17 2024
        Boot Method: UEFI
        24.11-RELEASE (amd64)
        FreeBSD 15.0-CURRENT
        CPU Type: Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz
        Current: 3606 MHz, Max: 3400 MHz
        4 CPUs : 1 package(s) x 4 core(s)

        GertjanG 1 Reply Last reply Reply Quote 0
        • GertjanG
          Gertjan @manjotsc
          last edited by

          @manjotsc said in DNS Stops working:

          When DNS is working I am able ping 1.1.1.1, but not when DNS stops.

          And what if 'DNS' (the resolver / unbound) is still working and your issue is the connection between the two devices ? NIC ? Cables ? switches ?

          Such a question would last a couple of minutes normally. You can be sure right away :

          When your 'ping 1.1.1.1' on a LAN based device "doesn't work", does it work on pfSense at that very moment (use the console ssh access, option 8) and execute the same command over there.
          To test DNS on pfSense, do a

          dig one.one.one.one +trace
          

          which will resolve from top to bottom.

          If ping using an IP, and using a host name, and the proposed DNS works on pfSense, you know now where to look ...

          Btw : DNS never stops working by itself, except :
          Bad uplink (WAN) connection.
          Some packages can receive settings that totally 'kill' pfSense, DNS, or the entire system. - The combination pfBlockerNG-devel <-> Unbound is very known.
          etc etc.

          No "help me" PM's please. Use the forum, the community will thank you.
          Edit : and where are the logs ??

          manjotscM 1 Reply Last reply Reply Quote 0
          • manjotscM
            manjotsc @Gertjan
            last edited by

            @Gertjan Alright I'll give a try when It goes down again, thanks.

            Vendor: HP
            Version: P01 Ver. 02.50
            Release Date: Wed Jul 17 2024
            Boot Method: UEFI
            24.11-RELEASE (amd64)
            FreeBSD 15.0-CURRENT
            CPU Type: Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz
            Current: 3606 MHz, Max: 3400 MHz
            4 CPUs : 1 package(s) x 4 core(s)

            1 Reply Last reply Reply Quote 0
            • S
              serbus
              last edited by

              Hello!

              Just a shot in the dark....

              In addition to pfb, are you running snort/suricata...with blocking turned on...and maybe some ET DNS type rules...?

              John

              Lex parsimoniae

              manjotscM 1 Reply Last reply Reply Quote 0
              • manjotscM
                manjotsc @serbus
                last edited by manjotsc

                @serbus I am not using snort or surcata,

                Vendor: HP
                Version: P01 Ver. 02.50
                Release Date: Wed Jul 17 2024
                Boot Method: UEFI
                24.11-RELEASE (amd64)
                FreeBSD 15.0-CURRENT
                CPU Type: Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz
                Current: 3606 MHz, Max: 3400 MHz
                4 CPUs : 1 package(s) x 4 core(s)

                manjotscM 1 Reply Last reply Reply Quote 0
                • manjotscM
                  manjotsc @manjotsc
                  last edited by manjotsc

                  @johnpoz @Gertjan @teamits @serbus It started happening again, this time instead of reboot pfsense or modem, I unplugged the Ethernet cable from wan port and plugged back in, everything start working again, so I replaced the cable just in case. But the issue remains, I have unplug and plug back the Ethernet cable from my modem to pfsense, to restore connectivity. The Internet cuts off on pfsense not only dns, when downloading large files.

                  Vendor: HP
                  Version: P01 Ver. 02.50
                  Release Date: Wed Jul 17 2024
                  Boot Method: UEFI
                  24.11-RELEASE (amd64)
                  FreeBSD 15.0-CURRENT
                  CPU Type: Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz
                  Current: 3606 MHz, Max: 3400 MHz
                  4 CPUs : 1 package(s) x 4 core(s)

                  1 Reply Last reply Reply Quote 0
                  • GertjanG
                    Gertjan
                    last edited by

                    You said 'modem' : is it really a modem ?
                    What is your pfSense WAN IP ? An RFC1918 or a "real Internet IP" ?

                    When you loose DNS, the resolver is still running ? You can, for example, use Diagnostics > DNS Lookup and lookup a local host like printer.localdomain.local (or whaterer your local domain is).

                    No "help me" PM's please. Use the forum, the community will thank you.
                    Edit : and where are the logs ??

                    manjotscM 1 Reply Last reply Reply Quote 0
                    • manjotscM
                      manjotsc @Gertjan
                      last edited by

                      @Gertjan I am extremely sorry about delayed reponse.

                      Annotation 2020-07-03 164730.png Annotation 2020-07-03 164507.png Annotation 2020-07-03 164435.png Annotation 2020-07-03 164241.png

                      Vendor: HP
                      Version: P01 Ver. 02.50
                      Release Date: Wed Jul 17 2024
                      Boot Method: UEFI
                      24.11-RELEASE (amd64)
                      FreeBSD 15.0-CURRENT
                      CPU Type: Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz
                      Current: 3606 MHz, Max: 3400 MHz
                      4 CPUs : 1 package(s) x 4 core(s)

                      1 Reply Last reply Reply Quote 0
                      • GertjanG
                        Gertjan
                        last edited by

                        Several questions back :

                        Why all the packages ? All the VPN's ?
                        Who is the user setup ? This is a router/firewall : the build user 'admin' will do just fine. A router is not a central meeting place.
                        As you can see, the "127.0.0.1" has no answer for any existing hostname, For me, all your test hostnames resolved just fine.

                        I advise you to tack a huge step back.
                        Save your config, and go back to default.
                        Take the initial setup as a reference : as it has one huge advantage : everything works. Especially DNS.
                        You do not need / should not add 24.225.128.24 / 24.200.0.2 / 24.55.0.19 / 1.1.1.1 / 1.0.0.1 except if you have your very special private reasons (making you an expert - the one that never asks questions because he "knows").

                        When all works fine, add, for example, one - just one - VPN. Test it, leave it some days. Check the logs for any entries you can't explain for yourself.
                        Then, do a next step. And again, take your time.

                        As soon as something goes bad, you will have that one-click solution to get back to a stable, working situational.

                        Btw : stay away form 'heavy' packages.

                        Btw : check your ISP / ISP equipment, like the upstream router.
                        this is bad to start with :

                        1c4c811d-fddc-4315-bd62-5938033e2d9f-image.png

                        No "help me" PM's please. Use the forum, the community will thank you.
                        Edit : and where are the logs ??

                        1 Reply Last reply Reply Quote 0
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