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    DNS_PROBE_FINISHED_NXDOMAIN sporadically for anywhere from 30secs to 10min. works flawlessly at all other times

    Scheduled Pinned Locked Moved DHCP and DNS
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    • R
      RickyBaker @SteveITS
      last edited by RickyBaker

      @SteveITS said in DNS_PROBE_FINISHED_NXDOMAIN sporadically for anywhere from 30secs to 10min. works flawlessly at all other times:

      Looks like your DHCP is set for a 2 hour lease (meaning 1 hour renewal). You could try extending that to say 8 or 12 hours.

      thanks, i'll look for that option and change it to 8

      @SteveITS said in DNS_PROBE_FINISHED_NXDOMAIN sporadically for anywhere from 30secs to 10min. works flawlessly at all other times:

      I don't see whether you posted you tried with DNSSEC disabled. Are you actually forwarding or not?

      98818954-e848-4537-a2eb-d62e8458bbb1-image.png
      is this option not showing up unticked in the logs? or is this screenshot suffice to say it's disabled.
      I don't think I'm forwarding?
      70b34280-03c4-4d33-b901-7b6329deff5e-image.png

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      • S
        SteveITS Galactic Empire @RickyBaker
        last edited by

        @RickyBaker said in DNS_PROBE_FINISHED_NXDOMAIN sporadically for anywhere from 30secs to 10min. works flawlessly at all other times:

        or is this screenshot suffice to say it's disabled.

        That's fine, I just didn't see a response above. Before 23.01 forwarding + DNSSEC didn't seem to be a problem but after 23.01 it often is.

        There's a checkbox in the resolver settings to forward but if DNSSEC is disabled that point is irrelevant.

        Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
        When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
        Upvote 👍 helpful posts!

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          RickyBaker @SteveITS
          last edited by

          @SteveITS Happened again this morning. Though just for my wife. She got DNS_PROBE_FINISHED_NXDOMAIN error in chrome but said the amazon link worked (so weird) but I did not experience any issues by the time i got a browser opened. This is the log for around that time:

          c835914c-7393-4661-afa7-004ff380ef85-image.png

          I did notice that attack from 180.101.88.225 with a Level 10 a LOT in the logs, is it possible my firewall has misidentified some of my devices as attackers? But then quickly resolves that's wrong before making the same mistake again soon?

          GertjanG S 2 Replies Last reply Reply Quote 0
          • GertjanG
            Gertjan @RickyBaker
            last edited by Gertjan

            @RickyBaker said in DNS_PROBE_FINISHED_NXDOMAIN sporadically for anywhere from 30secs to 10min. works flawlessly at all other times:

            180.101.88.225 with a Level 10 a LOT in the logs, is it possible my firewall has misidentified some of my devices as attackers?

            misidentified ?
            It's 180.101.88.225. No doubt about it.
            It that IP coming from your LAN ? Disconnect it, have it cleaned. Do have a talk with the owner.
            Is the IP coming from the Internet ? Empty the WAN firewall rule list, and you're good. I would fire the pfSense admin 😊

            edit : no LAN IP, whois told me "180.101.88.225" is Chinese allocated.
            Rip out your WAN cable now. We'll talk later ^^

            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 1
            • S
              SteveITS Galactic Empire @RickyBaker
              last edited by

              @RickyBaker the “now monitoring attacks” is logged whenever a log file rotates so is normal.

              The logged attacks though do indicate you have port 22 open on WAN, and check for other ports too, as that’s a good way to get hacked.

              Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
              When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
              Upvote 👍 helpful posts!

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              • R
                RickyBaker @SteveITS
                last edited by

                @SteveITS so close port 22 immediately?

                S GertjanG 2 Replies Last reply Reply Quote 0
                • S
                  SteveITS Galactic Empire @RickyBaker
                  last edited by

                  @RickyBaker I'd close all ports on WAN that are not needed. By default WAN has no rules so all incoming traffic from the Internet is blocked.

                  Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                  When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                  Upvote 👍 helpful posts!

                  R 1 Reply Last reply Reply Quote 1
                  • R
                    RickyBaker @SteveITS
                    last edited by

                    @SteveITS I certainly did not intentionally leave any ports open...Am firing up my VPN now...These logs are saying this IP is TRYING to access my network, not accessing it though right?

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                    • GertjanG
                      Gertjan @RickyBaker
                      last edited by

                      @RickyBaker
                      Not "closing".
                      Don't use any firewall rules that allow SSH access (port 22) or actually any access on the WAN interface.
                      Exactly like the way you found it, when installing pfSense.
                      No rules on WAN = safe.
                      Opening port 22 = "China" (the entire planet in reality) is lining up for you to 'try'.

                      There is an exception (as always) :
                      If you activate a VPN server (on pfSense), this will, by default, allow UDP traffic on port 1194 on the WAN interface.
                      If you need to access resources from the outside = WAN, use a VPN, or comparable.

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

                      R 2 Replies Last reply Reply Quote 1
                      • R
                        RickyBaker @Gertjan
                        last edited by

                        @Gertjan said in DNS_PROBE_FINISHED_NXDOMAIN sporadically for anywhere from 30secs to 10min. works flawlessly at all other times:

                        There is an exception (as always) :
                        If you activate a VPN server (on pfSense), this will, by default, allow UDP traffic on port 1194 on the WAN interface.
                        If you need to access resources from the outside = WAN, use a VPN, or comparable.

                        I do! there's always the concern i messed up during set up, but that was the intention. checking now

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                          RickyBaker @Gertjan
                          last edited by RickyBaker

                          @Gertjan 8a15c3c9-c8b8-4916-8326-e3a1cbbfba8a-image.png

                          f#$k this looks wide open. i dunno how that happened it says it comes from OpenVPN wizard. Is this wrong? Should Destination port be changed from asterix to 1194?

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                            RickyBaker @RickyBaker
                            last edited by

                            @RickyBaker 98817496-2147-4880-bab2-d5257a44fbf8-image.png
                            also, DEF didn't put in this rule, that ip address is my Synology box, think it added this rule via UPNP?

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                              SteveITS Galactic Empire @RickyBaker
                              last edited by SteveITS

                              @RickyBaker I would guess, it was edited at some point and the description remained. If you look at the rule without saving it, it will show a created and last saved date at the bottom.

                              Yes it should be 1194 UDP.

                              The floating rule could be from traffic shaping? (per the m_P2P text)

                              Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                              When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                              Upvote 👍 helpful posts!

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                                RickyBaker @SteveITS
                                last edited by

                                @SteveITS this look right then? a9f6421e-947c-402a-b6fb-d9b7f6156c5b-image.png

                                disabled the floating rule and made this change and still have access to the pfsense remotely so seems to not have broken the openvpn connection, thank you for the confirmation.

                                I would LOVE to do traffic shaping but I have not actually attempted it in many years and recently redid all the rules to add VLANs so i'm very puzzled by this (I also don't even use the Synology really) but you are absolutely right that qP2P sure looks like a traffic shaping effort...very disconcerting

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                                  SteveITS Galactic Empire @RickyBaker
                                  last edited by

                                  @RickyBaker yes that looks better and will not allow connections to 22/80/443.

                                  What is the date on the floating rule? (bottom of the edit rule page)

                                  Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                                  When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                                  Upvote 👍 helpful posts!

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                                  • R
                                    RickyBaker @SteveITS
                                    last edited by

                                    @SteveITS that's it, Created and Updated 2/4/17 by Traffic Shaper Wizard. That was pre kids and pre VPN. Thanks for teaching me that trick. happy to just disable, possibly just delete

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                                      RickyBaker @SteveITS
                                      last edited by RickyBaker

                                      @SteveITS thanks so much for your help with this. Assuming for the best that the attacker was not able to gain access, what is my next steps? Could this have caused my weird DNS/DHCP problems or is this just a "happy" coincidence that y'all helped me find this vulnerability.

                                      Currently tracking down the 4 DHCP leases that aren't statically assigned. FIgured out 2 of them, need to google Part II research for the 3rd and the 4th was idle so i just booted it

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                                        SteveITS Galactic Empire @RickyBaker
                                        last edited by

                                        @RickyBaker I think it's just a coincidence but a fortunate one.

                                        Is there anything notable in the DNS Resolver log when the outage happens?

                                        Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                                        When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                                        Upvote 👍 helpful posts!

                                        R 1 Reply Last reply Reply Quote 1
                                        • R
                                          RickyBaker @SteveITS
                                          last edited by

                                          @SteveITS

                                          bf5bdd84-5b10-451d-929a-4905253c5c3b-image.png

                                          The final device has this mac address manufacturer. The most common device seems to be a Dreo fan (which I don't have). Googling isn't ringing any bells and pointing to the IP address doesn't give me a splash page or anything. Any advice on blocking just this mac address so I can see what breaks?

                                          @SteveITS said in DNS_PROBE_FINISHED_NXDOMAIN sporadically for anywhere from 30secs to 10min. works flawlessly at all other times:

                                          Is there anything notable in the DNS Resolver log when the outage happens?

                                          99001454-d720-4410-8af7-1d186f4c7d1e-image.png

                                          Surprisingly sparse....

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                                            RickyBaker @RickyBaker
                                            last edited by

                                            @RickyBaker the DHCP log seems like all the same as well:
                                            6717aaea-19ad-4d02-a59c-4c7dd5afaf8c-image.png

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