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    Frequent DNS timeouts

    Scheduled Pinned Locked Moved pfBlockerNG
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    • S
      SteveITS Galactic Empire @oopohj5Oo8shieZe1ree
      last edited by

      @oopohj5oo8shieze1ree There was a post today that 'Disabling "Use SSL/TLS for outgoing DNS Queries to Forwarding Servers"' helped that person.

      https://forum.netgate.com/post/1090876

      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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        SteveITS Galactic Empire @oopohj5Oo8shieZe1ree
        last edited by

        Also there's a fix for Unbound not correctly binding to "All" interfaces on IPv6.

        https://forum.netgate.com/topic/176989/problems-with-pfsense-ipv6-dns-function-does-it-exist/36

        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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          oopohj5Oo8shieZe1ree @SteveITS
          last edited by

          @steveits Thanks for pointing me to the other threads.

          I'm thinking of just giving up on using forwarding. I need to figure out if my ISP limits access to DNS servers when not forwarding.

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            oopohj5Oo8shieZe1ree
            last edited by

            After turning off DNS forwarding, resolution was nearly instantaneous for a couple of days. But the random timeouts have returned.

            I don't see anything in the logs to indicate something is failing.

            Can someone point me to a DNS debugging guide or something that will help me figure out what the root cause is here.

            Thank you.

            S 1 Reply Last reply Reply Quote 0
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              SteveITS Galactic Empire @oopohj5Oo8shieZe1ree
              last edited by

              @oopohj5oo8shieze1ree There are a few here:
              https://docs.netgate.com/pfsense/en/latest/troubleshooting/index.html#dns

              Also take a look through https://forum.netgate.com/category/19/dhcp-and-dns as there are other posts for 23.01.

              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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                thundergate @oopohj5Oo8shieZe1ree
                last edited by

                @oopohj5oo8shieze1ree

                Hi. Do have nearly the same issues.

                But for me I don't use and DNS forwarding or anything else. Just pfSense Unbound in combination with pfBlockerNG.

                Don't have any DNS fails at all. But looks like name resolution does hang after some amount of time. After that it looks like it is cached again and resolution works fine.
                But I do have this issues nearly every day.

                Something like a cleared unbound cache - what's not the case.

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

                  @thundergate said in Frequent DNS timeouts:

                  cleared unbound cache

                  This can only happens when the resolver -unbound is told to stop, or restart, which is a controlled stop, to be started right afterwards.
                  It can take several seconds to do so.
                  The cache will be lost, but subsequent DNS resolving won't take long, typical is a fraction of a second.

                  If unbound restarts happen very often, you can start to 'feel' the absence of the DNS sub system.

                  So, ask your pfSense how often it restarts :

                  grep "Restart" /var/log/resolver.log
                  

                  If it's just couple of times a day (lesser == better) : this is not your issue.

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

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                    oopohj5Oo8shieZe1ree @SteveITS
                    last edited by

                    @steveits After switching from forwarding to normal resolving I let things sit for a bit to see what would happen. It looks like unbound is restarting a lot:

                    Mar 15 08:01:04 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:08:33 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:12:20 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:12:45 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:13:39 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:29:45 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:34:44 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:35:41 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:42:09 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:42:34 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:49:47 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    Mar 15 08:52:13 netgate unbound[20724]: [20724:0] notice: Restart of unbound 1.17.1.
                    

                    Is there a known workaround for this?

                    S T 2 Replies Last reply Reply Quote 0
                    • S
                      SteveITS Galactic Empire @oopohj5Oo8shieZe1ree
                      last edited by

                      @oopohj5oo8shieze1ree The most common cause for restarts is having DHCP set to register DHCP leases in DNS, which triggers a restart after each and every DHCP lease. Options are to not do that, or to make the lease long enough that it renews in "days" not "hours." (renewal is 1/2 of the lease duration)

                      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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                      • O
                        oopohj5Oo8shieZe1ree
                        last edited by

                        @steveits I believe I have that turned off (in Services -> DHCP Server -> Dynamic DNS ->
                        Enable registration of DHCP client names in DNS). However, it does appear to be registering DHCP host names with the DNS server regardless of this setting.

                        I've increased the lease time and will report back.

                        Thank you.

                        johnpozJ 1 Reply Last reply Reply Quote 0
                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @oopohj5Oo8shieZe1ree
                          last edited by

                          @oopohj5oo8shieze1ree unbound starting that often is going to be problematic that is for sure..

                          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
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                            thundergate @oopohj5Oo8shieZe1ree
                            last edited by

                            @oopohj5oo8shieze1ree

                            Same for me - a lot of unbound restarts and I actually don't know why?!

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

                              @thundergate well no restarts here

                              [23.01-RELEASE][admin@sg4860.local.lan]/root: unbound-control -c /var/unbound/unbound.conf status
                              version: 1.17.1
                              verbosity: 1
                              threads: 4
                              modules: 2 [ validator iterator ]
                              uptime: 196553 seconds
                              options: control(ssl)
                              unbound (pid 56217) is running...
                              [23.01-RELEASE][admin@sg4860.local.lan]/root:
                              

                              196K seconds - 54 hours... Which was when I restarted pfsense to fix my swap not showing on widget..

                              If unbound is restarting - especially that often, your not going to have a good time.. You need to figure out why its restarting, registration of dhcp is typical reason you would see restarts like that..

                              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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                                thundergate @johnpoz
                                last edited by thundergate

                                @johnpoz Hm. Ok.

                                Did you enable those settings within unbound?

                                SCR-20230315-qoem.png

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

                                  @thundergate no - it has been a known issue for years that registering dhcp restarts unbound. I only register static mappings

                                  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

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

                                    @johnpoz said in Frequent DNS timeouts:

                                    known issue for years that registering dhcp restarts unbound

                                    ref: https://redmine.pfsense.org/issues/5413

                                    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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                                    • T
                                      thundergate @johnpoz
                                      last edited by

                                      @johnpoz 🤦 Oh no - That's stupid?!

                                      But I do need those DHCP leases to be seen to know what device does make all those requests.... Cannot stand with IP addresses only.

                                      Used OPNsense before - but didn't had those issues, if I remember correctly?

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

                                        @thundergate Then until resolved, as I noted above make your lease time longer. It will restart on average every ( (lease duration/2) / # leases ).

                                        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!

                                        T 1 Reply Last reply Reply Quote 0
                                        • T
                                          thundergate @SteveITS
                                          last edited by

                                          @steveits Will have to look into it.

                                          I'm quite disappointed. Never thought that such an error does exist within pfSense (and it does exist since a few years now).

                                          Are you all not interested in name resolution and do only handle IPs?

                                          For me unbound restarts every 2-5 minutes (doesn't look like it is the DHCP lease issue at all?!).

                                          johnpozJ S 3 Replies Last reply Reply Quote 0
                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator @thundergate
                                            last edited by

                                            @thundergate said in Frequent DNS timeouts:

                                            re you all not interested in name resolution and do only handle IPs?

                                            All of the devices I have that I need to resolve or want to resolve via name I have reserved IP for ;)

                                            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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