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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 @Gertjan
      last edited by

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

      You can. DNSSEC, if activated, uses Python. And pfBlockerng - but you don't use pfBlockerng .
      It's activated by default.

      any suggestions on what options to select for the Python Module after enabling? If I understood you correctly you were suggesting that it's necessary IF i enable DNSSEC support? But that DNSSEC isn't necessary?

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

      Pick one you've listed. Certs are not used by default.

      I picked my name, which was a user I created for OpenVPN i think. I assumed you were implying that picking "Webconfigurator Default" was suboptimal/wrong?

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

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

        any suggestions

        119744a1-3ece-4254-a444-2284b83e440e-image.png

        The resolver can do DNSSEC for you. It's not mandatory.
        But If you know what DNSSEC is, you will activate DNSSEC. It will not secure every DNS request, as most domain names are not signed yet. But when they are, why not securing the request ?

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

        I picked my name

        TLS can be used by unbound to secure the TLS channels, like the control chancel, commonly on 853. Any cert will do.

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

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

          The cert means nothing - unless you want unbound to be a dot server to your clients. Forget about the cert that is listed. It matters when you want to answer dot queries, not when you want to make 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 2.7.2, 24.11

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          • R
            RickyBaker @johnpoz
            last edited by

            @johnpoz @Gertjan thanks all

            I've enabled DNSSEC again since it didn't really help my issue having it disabled. Is there another log I should increase the logging on? What level should I have the dns resolver on? I'm still experiencing the issue, yesterday for about 20 minutes (longest yet) I couldn't' open a webpage on my phone, but I was concurrently streaming the Knicks game on Youtube TV.

            I've also added all those "no vendor" Mac address's I couldn't explain with randomly assigned DHCP leases to the whitelist block list and they've yet to come back and I've yet to discover anything broken. Just an update.

            Any advice on getting it updated to 2.7.2 without doing a full clean install and restore?

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

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

              I've enabled DNSSEC again since it didn't really help my issue having it disabled

              if you are forwarding dnssec should be disabled.. While it might not seem like no issues with a few queries, but can tell you its going to be problematic at some point.. even quad9 faq for when forwarding says to disable it. It is pointless if you forward, where you forward does dnssec or they don't you telling unbound to do it isn't going to do anything other than cause you issues at some point.

              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 2.7.2, 24.11

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

                @johnpoz I'm no longer forwarding per your first post in this thread.

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

                  @RickyBaker Long thread and haven't paid close attention, could tell if you had switched back to forwarding or not. Yeah if your resolving then dnssec is good to have enabled.

                  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 2.7.2, 24.11

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

                    @johnpoz great thanks for circling back

                    R 1 Reply Last reply Reply Quote 0
                    • R
                      RickyBaker @RickyBaker
                      last edited by

                      https://pastebin.com/SFR8BXb0

                      Woke up from a nap and experienced one of the longest internet outages of this whole saga. It was out at 3:14 when I tried to open venmo and was out for over 20 minutes before it came back. the above is the DNS resolver log but I think i have the log level dialed too high cause 2000 entries didn't even go back 2 minutes. I've changed it back to Log Level 1 but could someone check it out and see if there's any clues in there (or what log level I should have it at)? Or is there another log that I should also be monitoring? Is it possible the problem is purely something with the wifi and Ubiquiti?

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

                        @RickyBaker

                        Same thoughts here : a high level of log details actually the details your looking for, as there is only for 2 minutes worth of info.
                        If you have some disk space left, you can make the log files bigger.

                        48bc948c-57dc-4564-b2e1-9af964888543-image.png

                        If needed, you can make the log retention a bit smaller - I've "7", you can make it 5 or 4.

                        You can also make this, one

                        0bc21cb3-4150-4daf-922f-0b75f6638b5d-image.png

                        a bit bigger.

                        The actual goal is :
                        As soon as you find a situation where a device has no access anymore, you have to check :
                        Does the access without using DNS works ? For example, ping 8.8.8.8 from that device.
                        Also double check : does the device has a valid IP, gateway and dns set at that moment ?
                        Example :

                        ipconfig /all
                        

                        and check the duration of the lease, the gateway, the DNS (both should point to the IP of pfSense.

                        Check on the device if "DNS" works :

                        C:\Users\Gauche>nslookup www.google.com
                        Serveur :   pfSense.bhf.tld
                        Address:  2a01:cb19:907:bedf:92ec:77ff:fe29:392c
                        
                        Réponse ne faisant pas autorité :
                        Nom :    www.google.com
                        Addresses:  2a00:1450:4007:81a::2004
                                  142.250.201.164
                        

                        Take note : for me, both IPv6 and IPv4 works.

                        Then (also) check on pfSense if resolving works :

                        dig @127.0.0.1 www.google.com +short
                        

                        and then

                        dig @192.168.1.1 www.google.com +short
                        

                        where 192.168.1.1 is your LAN interface.

                        Check if unbound is up and running :

                        [24.03-RELEASE][root@pfSense.bhf.tld]/root: ps ax | grep 'unbound'
                        74113  -  Ss       4:32.60 /usr/local/sbin/unbound -c /var/unbound/unbound.conf
                        ....
                        ....
                        

                        and

                        [24.03-RELEASE][root@pfSense.bhf.tld]/root: sockstat | grep 'unbound'
                        unbound  unbound    74113 3   udp6   *:53                  *:*
                        unbound  unbound    74113 4   tcp6   *:53                  *:*
                        unbound  unbound    74113 5   udp4   *:53                  *:*
                        unbound  unbound    74113 6   tcp4   *:53                  *:*
                        unbound  unbound    74113 9   tcp4   127.0.0.1:953         *:*
                        ...
                        ...
                        ...
                        ...
                        

                        With the unbound log details set to "1", it will still contains the number of restarts (a controlled stop and then a start :

                        grep "stopped" /var/log/resolver.log
                        .....
                        
                        <30>1 2024-05-06T00:15:24.852356+02:00 pfSense.bhf.tld unbound 12814 - - [12814:0] info: service stopped (unbound 1.19.3).
                        

                        Btw : the actual unbound version is 1.19.3 as I'm using 24.03.
                        pfSense 2.8.0 will be coming out soon.
                        Not that the version really matters (imho) as I was using 1.17.x also a long time, and don't recall having any issues.

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

                        Is it possible the problem is purely something with the wifi and Ubiquiti?

                        For me, an AP should be what it should do :; being a radio to wire signal converter.
                        True, an AP can do a lot more, and really braking the connection for you.
                        When testing connectivity issues, add APs and other gadgets later on, when you know the wired connection works well.
                        The same thing goes for L3 'smart, VLAN based' switches : only use the when the bare bone network works well.

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

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

                          @RickyBaker did you actually do some dns queries while you were having the issue, to both unbound and say external dns?

                          You should log queries and replies as well if your wanting to troubleshoot dns not working.

                          int your options box in unbound

                          server:
                          log-queries: yes
                          log-replies: yes
                          

                          what is the response, timeout talking to unbound, servfail, nx?

                          fire up your fav dns tool, nslookup, dig, doggo, host, etc. and actual validate what is failing.. If you look some fqdn do you get a response. if so what is the response, did it work, did unbound return servfail, or nx domain ?

                          Does unbound answer local resources, like pfsense fqdn? Does something that is cached work, only new queries fail. You can view what is in your cache

                          [23.09.1-RELEASE][admin@sg4860.home.arpa]/root: unbound-control -c /var/unbound/unbound.conf dump_cache | grep forum.netgate.com
                          forum.netgate.com.      2452    IN      A       208.123.73.71
                          msg forum.netgate.com. IN A 32896 1 2452 3 1 1 3 6 
                          forum.netgate.com. IN A 0
                          [23.09.1-RELEASE][admin@sg4860.home.arpa]/root: 
                          

                          If that fails, then do a query directed to some external NS like quad9 or google - do those work?

                          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 2.7.2, 24.11

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                          • 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:

                            As soon as you find a situation where a device has no access anymore, you have to check :
                            Does the access without using DNS works ? For example, ping 8.8.8.8 from that device.
                            Also double check : does the device has a valid IP, gateway and dns set at that moment ?

                            this is really helpful, thank you, i will try to screenshot this post and enact it as well as possible the minute i notice an outage. BTW I tested a hard wired PC when i had an outage and also observed dns connectivity issues fwiw. but all of this is a very good framework for continuing the troubleshooting

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

                              @RickyBaker how are you knowing the dns is failing? Are you doing an actual query with a tool? like dig or nslookup?

                              Or your browser just doesn't load - for all you know your browser is using doh..

                              When you have the issue, can your client ping its gateway (pfsense) can you ping the internet via IP, 8.8.8.8 for example.

                              If you can not ping pfsense, then you have a local network issue most likely. If you can not ping the internet - maybe just your internet is out. If you can ping pfsense, can you do a query for pfsense name, this should always work even if the internet is down. Only reason it wouldn't is you can't actually talk to pfsense, or unbound is not running.

                              Doing some basic connectivity tests and dns queries should point to where your actual problem is.

                              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 2.7.2, 24.11

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                              • R
                                RickyBaker @johnpoz
                                last edited by

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

                                did you actually do some dns queries while you were having the issue, to both unbound and say external dns?

                                at one point when i finally realized i could use dig on the pfsense itself I ran the command you posted to 8.8.8.8 and it worked successfully but I need to test this more thoroughly (i.e. other linux devices not the pfsense) and try 8.8.8.8 as well as google.com. thanks for reminding.

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

                                int your options box in unbound

                                I'm sorry where would i find/set these options set?

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

                                what is the response, timeout talking to unbound, servfail, nx?

                                again, very sorry but how would I do this? I don't even KNOW what servfail, nx is? In fact, reading the rest of the suggestions i can tell this is an important framework for isolating the issue but it's just far beyond my grasp of the tools at play. I will google each individual term in hopes of understanding better but if there's a more specific you could include for me to enact and post that would be very helpful.

                                S 1 Reply Last reply Reply Quote 0
                                • S
                                  SteveITS Galactic Empire @RickyBaker
                                  last edited by

                                  @RickyBaker Windows has nslookup...run "nslookup netgate.com" and see what it returns. Do the same with "dig netgate.com" on the router, and/or use Diagnostics/DNS Lookup to test there.

                                  Servfail is an error. NXDOMAIN means the host doesn't exist.

                                  At the time of the outage also "ping 8.8.8.8" to ensure your Internet is working, even if DNS is not.

                                  In other words try to narrow down your problem.

                                  re: options, he means the settings in Services/DNS Resolver under "Display Custom Options" which is blank by default.

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

                                    s. Do the same with "dig netgate.com" on the router, and/or use Diagnostics/DNS Lookup to test there.

                                    great, thanks for that explanation

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

                                      @RickyBaker also when your dig, make sure its pointed to pfsense IP with an at.. Linux likes to use 127.0.0.53 which doesn't really tell you who got asked. So put the @ipaddress in your query..

                                      example

                                      user@UC:~$ dig www.netgate.com
                                      
                                      ; <<>> DiG 9.18.18-0ubuntu0.22.04.2-Ubuntu <<>> www.netgate.com
                                      ;; global options: +cmd
                                      ;; Got answer:
                                      ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 14863
                                      ;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1
                                      
                                      ;; OPT PSEUDOSECTION:
                                      ; EDNS: version: 0, flags:; udp: 65494
                                      ;; QUESTION SECTION:
                                      ;www.netgate.com.               IN      A
                                      
                                      ;; ANSWER SECTION:
                                      www.netgate.com.        30      IN      CNAME   1826203.group3.sites.hubspot.net.
                                      1826203.group3.sites.hubspot.net. 30 IN CNAME   group3.sites.hscoscdn00.net.
                                      group3.sites.hscoscdn00.net. 30 IN      A       199.60.103.30
                                      group3.sites.hscoscdn00.net. 30 IN      A       199.60.103.226
                                      
                                      ;; Query time: 12 msec
                                      ;; SERVER: 127.0.0.53#53(127.0.0.53) (UDP)
                                      ;; WHEN: Mon May 06 15:21:41 CDT 2024
                                      ;; MSG SIZE  rcvd: 160
                                      
                                      user@UC:~$ 
                                      

                                      You don't what ns it actually asked.. so do

                                      user@UC:~$ dig @192.168.2.253 www.netgate.com
                                      
                                      ; <<>> DiG 9.18.18-0ubuntu0.22.04.2-Ubuntu <<>> @192.168.2.253 www.netgate.com
                                      ; (1 server found)
                                      ;; global options: +cmd
                                      ;; Got answer:
                                      ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 19274
                                      ;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1
                                      
                                      ;; OPT PSEUDOSECTION:
                                      ; EDNS: version: 0, flags:; udp: 4096
                                      ;; QUESTION SECTION:
                                      ;www.netgate.com.               IN      A
                                      
                                      ;; ANSWER SECTION:
                                      www.netgate.com.        3553    IN      CNAME   1826203.group3.sites.hubspot.net.
                                      1826203.group3.sites.hubspot.net. 3553 IN CNAME group3.sites.hscoscdn00.net.
                                      group3.sites.hscoscdn00.net. 3553 IN    A       199.60.103.30
                                      group3.sites.hscoscdn00.net. 3553 IN    A       199.60.103.226
                                      
                                      ;; Query time: 4 msec
                                      ;; SERVER: 192.168.2.253#53(192.168.2.253) (UDP)
                                      ;; WHEN: Mon May 06 15:22:28 CDT 2024
                                      ;; MSG SIZE  rcvd: 160
                                      
                                      user@UC:~$ 
                                      

                                      Where 192.168.2.253 is the IP address of pfsense..

                                      You can normally see where 127.0.0.53 is forwarding to with

                                      user@UC:~$ resolvectl status
                                      Global
                                             Protocols: -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
                                      resolv.conf mode: stub
                                      
                                      Link 2 (ens3)
                                          Current Scopes: DNS
                                               Protocols: +DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
                                      Current DNS Server: 192.168.3.10
                                             DNS Servers: 192.168.3.10
                                              DNS Domain: home.arpa
                                      user@UC:~$ 
                                      

                                      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 2.7.2, 24.11

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                                      • R
                                        RickyBaker @johnpoz
                                        last edited by

                                        @johnpoz thanks, this is very helpful, i will race to enact during the next outing and repost here. thanks for your patience.

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                                        • R
                                          RickyBaker @johnpoz
                                          last edited by

                                          @johnpoz couldn't get to a laptop fast enough yesterday to enact these troubleshooting steps but I was able to fire up a local session on juicessh on my phone:

                                          ping googlens

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

                                            @RickyBaker

                                            and you stopped testing ...
                                            That laptop moved that fast ??
                                            No more issues right after the ping google test ?

                                            You don't need to react 'fast', as the logs, example : unbound /var/log/resolver/log and the /var/log/system = system logs are there for days.

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

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