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    DNS randomly stops working

    Scheduled Pinned Locked Moved DHCP and DNS
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    • J
      juniper @SashLi
      last edited by

      @sashli try to ping other interfaces from pfsense itself...

      i think is jail related or something similar...

      S 1 Reply Last reply Reply Quote 0
      • S
        SashLi @juniper
        last edited by

        @juniper just found this ticket in redmine, not sure if this can be an issue created by this gatewax problem

        IPv4 link-local (169.254.x.x) gateway does not function

        J GertjanG 3 Replies Last reply Reply Quote 0
        • J
          juniper @SashLi
          last edited by

          @sashli i don't know...

          I can add an information, my pfsense installation is on proxmox ve virtual machine.

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

            @sashli said in DNS randomly stops working:

            @juniper just found this ticket in redmine, not sure if this can be an issue created by this gatewax problem

            IPv4 link-local (169.254.x.x) gateway does not function

            That's a special case, using IP's like 169.254.0.0/16.
            There is a small patch for this - jimp posted one yesterday.

            I've updated my pfSense at home (Hyper-V = VM) based : it's just perfect.
            I've just updated my work pfSense, they update went just fine. Again perfect.

            127.0.0.1 isn't even an external driver related, as it is part of the build in 'kernel' IP stack facilities.

            Use another VM host - if you have a Windows 10 Pro somewhere, you could make one right away, or install pfSense bare bone and you see that their is - can not be - localhost issues, as it will break everything.

            Just to be sure : your issue exists after you reset to default - and you only changed the password (!! did NOT import your settings !!) ?

            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
            • J
              juniper @SashLi
              last edited by

              @sashli

              Problem appear if i insert 127.0.0.1 on GENERAL SETUP---DNS Server Settings

              I use to have there 127.0.0.1 if pfsense is a dns resolver.

              If i config with 127.0.0.1 GENERAL SETUP---DNS Server Settings as a default pfsense dns server there is the problem with interface lo0.

              Cool_CoronaC GertjanG 2 Replies Last reply Reply Quote 0
              • Cool_CoronaC
                Cool_Corona @juniper
                last edited by

                @juniper Then you create a loopback??

                If nothing is in General setup then it uses localhost.

                J 1 Reply Last reply Reply Quote 0
                • J
                  juniper @Cool_Corona
                  last edited by

                  @cool_corona no i use 127.0.0.1 as dns resolver for pfsense.

                  Cool_CoronaC 1 Reply Last reply Reply Quote 0
                  • Cool_CoronaC
                    Cool_Corona @juniper
                    last edited by

                    @juniper Leave it blank and

                    c42bdb5c-69d0-4613-aaa1-c3ee3c07a586-billede.png

                    And reboot

                    J 1 Reply Last reply Reply Quote 0
                    • J
                      juniper @Cool_Corona
                      last edited by

                      @cool_corona yes it works!

                      Problem appear if i use 127.0.0.1 in general setup.

                      If i set an external dns and set dns resolution behavior as you suggest all working fine.

                      Thank you.

                      S 1 Reply Last reply Reply Quote 0
                      • S
                        SashLi @juniper
                        last edited by

                        @juniper exactly its a problem when 127.0.0.1 is listed in the general setup of the DNS server list.

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

                          @juniper

                          Why do you want to add 127.0.0.1 here :

                          3197d809-b8b8-429c-a2ea-0c84b2205d2d-image.png

                          ?

                          As you can see, I have nothing.
                          Because that's default : nothing.

                          Still, the magic is happening :

                          68290cff-a748-408d-982a-c8786d8d29b0-image.png

                          I hope (didn't test) that pfSense is intelligent enough that, when 127.0.0.1 is added here :
                          5b501b55-8d28-4178-bd89-5705249afe46-image.png

                          It will ignore that 'request' as 127.0.0.1 is already there.
                          Here it is :
                          /etc/resolv.conf .......

                          nameserver 127.0.0.1
                          search your-domain.tld
                          

                          Ok, I broke my won rules ™ © and added some DNS settings myself.

                          9b5470ef-d9e7-47a1-8158-ea67587c4040-image.png

                          5878155b-aae4-4e95-b20c-414957138a27-image.png

                          but /etc/resolv.conf didn't change.
                          I'm missing something ....

                          But pfSense (unbound) works.

                          edit : this is a no go :

                          [2.5.1-RELEASE][admin@pfsense.my-domain.tld]/root: dig @127.0.0.1 google.com
                          net.c:536: probing sendmsg() with IP_TOS=b8 failed: Can't assign requested address
                          net.c:536: probing sendmsg() with IPV6_TCLASS=b8 failed: No route to host

                          Ok. Great.
                          Who calls Houston ?

                          Solution : remove ::1 and 127.0.0.1 from the General settings as it was
                          Useless (before)
                          Break things (today).

                          So, please : don't do that ;)

                          edit : even why I removed ::1 and 127.0.0.1 I had could not use "127.0.0.1" any more.

                          It was :

                          net.c:536: probing sendmsg() with IP_TOS=b8 failed: Can't assign requested address
                          

                          all the time now.

                          Si, guys,I don't quiet understand what I'm seeing, but I see what you see.

                          Unbound wasn't listening to 127.0.0.1 any more - I restarted unbound : didn't help. I had to restart "127.0.0.1" - if possible.
                          I had to reboot pfSense - as this is a way to 'restart' the kernel.

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

                          E 1 Reply Last reply Reply Quote 1
                          • E
                            e-1-1 @Gertjan
                            last edited by

                            @gertjan Personally had 127.0.0.1 from before that "DNS Resolution Behavior" section existed, a couple of years at least.
                            If memory serves right 🤔
                            Guess that's because we wanted to ensure the system used its own resolver, and that only.

                            Was stunned when all DNS resolution stopped after upgrading to 2.5.1. Not even pkg worked :)
                            But some dig(ging) lead to the entry removal, then restoration of DNS service.

                            No bug listed as of now that I can find, but @jimp could we have this case covered in the pfsense-upgrade script that gets updated when pressing "13" in the CLI? It would eliminate the 127.0.0.1 entry, as workaround for now in place of debugging the lovely

                            net.c:536: probing sendmsg() with IP_TOS=b8 failed: Can't assign requested address
                            

                            bork message.

                            1 Reply Last reply Reply Quote 0
                            • C
                              collinatselect
                              last edited by collinatselect

                              I am also having this problem after upgrading directory from 2.4.5 CE to 2.5.1 on a Sophos SG-210.
                              In my case, enabling unbound on the Service Watchdog list restarts the service, but then the CPU is pegged at 100% and resolution still doesn't happen. Restarting the firewall works. I have not yet checked the PID or socket status during an outage, but I suspect unbound crashes, thinks its still running but can't clean itself up.

                              One thing I noticed on my system is pkg info unbound says Python is enabled, even though it is disabled in the configuration. I manually restarted after toggling Python on and off. Is this even relevant?

                              [2.5.1-RELEASE][admin@myfirewallnotyours]/root: pkg info unbound
                              unbound-1.13.1
                              Name           : unbound
                              Version        : 1.13.1
                              Installed on   : Thu Apr 15 03:10:26 2021 CDT
                              Origin         : dns/unbound
                              Architecture   : FreeBSD:12:amd64
                              Prefix         : /usr/local
                              Categories     : dns
                              Licenses       : BSD3CLAUSE
                              Maintainer     : jaap@NLnetLabs.nl
                              WWW            : https://www.nlnetlabs.nl/projects/unbound
                              Comment        : Validating, recursive, and caching DNS resolver
                              Options        :
                                      DNSCRYPT       : off
                                      DNSTAP         : off
                                      DOCS           : off
                                      DOH            : on
                                      ECDSA          : on
                                      EVAPI          : off
                                      FILTER_AAAA    : off
                                      GOST           : on
                                      HIREDIS        : off
                                      LIBEVENT       : on
                                      MUNIN_PLUGIN   : off
                                      PYTHON         : on
                                      SUBNET         : off
                                      TFOCL          : off
                                      TFOSE          : off
                                      THREADS        : on
                              Shared Libs required:
                                      libexpat.so.1
                                      libnghttp2.so.14
                                      libpython3.7m.so.1.0
                                      libevent-2.1.so.7
                              Shared Libs provided:
                                      libunbound.so.8
                              Annotations    :
                                      FreeBSD_version: 1202504
                                      cpe            : cpe:2.3:a:nlnetlabs:unbound:1.13.1:::::freebsd12:x64
                                      repo_type      : binary
                                      repository     : pfSense
                              Flat size      : 7.79MiB
                              

                              Tried all recommendations on this post but nothing is working so far.

                              1 Reply Last reply Reply Quote 1
                              • J
                                JasonAU
                                last edited by

                                Eagerly following any threads about DNS, My watch dog is restarting Unbound all the time.

                                2.5.1-RELEASE (amd64)
                                pfBlockerNG-devel: 3.0.0_16
                                snort: 4.1.3_5
                                Telegraf: 0.9_5

                                Just wanted to share what see just on the off chance it helps the group, I did notice the already in use error in my system logs, when the watch dog is trying to start it back up

                                Apr 23 10:15:04 pfsense php[92161]: servicewatchdog_cron.php: The command '/usr/local/sbin/unbound -c /var/unbound/unbound.conf' returned exit code '1', the output was '[1619136904] unbound[68018:0] debug: creating udp4 socket 192.168.1.1 53 [1619136904] unbound[68018:0] error: bind: address already in use [1619136904] unbound[68018:0] fatal error: could not open ports'
                                Apr 23 10:15:04 pfsense php[73303]: notify_monitor.php: Message sent to XXXXX@hotmail.com OK
                                Apr 23 10:15:01 pfsense php[92161]: servicewatchdog_cron.php: Service Watchdog detected service unbound stopped. Restarting unbound (DNS Resolver)
                                

                                Brisbane Queensland Australia

                                GertjanG 1 Reply Last reply Reply Quote 0
                                • C
                                  collinatselect
                                  last edited by

                                  Hi, so this is a documented upstream bug.
                                  https://redmine.pfsense.org/issues/11316
                                  I just found out about it because I submitted a trouble ticket.
                                  Unfortunately, until this regression is fixed, the solution is either

                                  1. Turn of Register "DHCP leases in DNS"
                                  2. Downgrade to 2.4.5
                                  3. Downgrade the package
                                  4. use the DNS forwarder

                                  Unfortunately 1) and 4) don't help if you need to Register DHCP in DNS in your organization.

                                  So here's hoping the developers on unbound have an easy fix.

                                  N 1 Reply Last reply Reply Quote 0
                                  • N
                                    netblues @collinatselect
                                    last edited by

                                    Service watchdog and unbound don't play well together.
                                    Especially if pfblockerng is also used (since it does take time to come up)
                                    In various situations, it ends up in unbound restart loops.

                                    By enabling unbound python mode, and disabling dhcp integration, unbound is stable.
                                    However, if wan ip changes due to pppoe restarting, unbound will die.
                                    Always.
                                    And since service watchdog is a no go for unbound, it has to be restarted manually
                                    Yikes!.
                                    At the time of ppp restart I get this
                                    Apr 19 11:18:24 unbound 19913 [19913:0] info: service stopped (unbound 1.13.1).
                                    2.5.1 pfblockerngng 3.0.16

                                    bingo600B J 2 Replies Last reply Reply Quote 1
                                    • bingo600B
                                      bingo600 @netblues
                                      last edited by

                                      @netblues

                                      I'm using unbound & service watchdog , and have no isues.
                                      Not using pfblocker though.

                                      If you find my answer useful - Please give the post a 👍 - "thumbs up"

                                      pfSense+ 23.05.1 (ZFS)

                                      QOTOM-Q355G4 Quad Lan.
                                      CPU  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                                      LAN  : 4 x Intel 211, Disk  : 240G SAMSUNG MZ7L3240HCHQ SSD

                                      1 Reply Last reply Reply Quote 0
                                      • J
                                        JasonAU @netblues
                                        last edited by

                                        @netblues said in DNS randomly stops working:

                                        However, if wan ip changes due to pppoe restarting, unbound will die.
                                        Always.

                                        Hmm that interesting, for me I have noticed when watchdog finds unbound is broken I also see logs saying my Nord VPN got a new IP.. the core WAN (ppoe) is up but one of the VPNs out drop or looses some packets around the same time

                                        Brisbane Queensland Australia

                                        1 Reply Last reply Reply Quote 0
                                        • G
                                          grumple
                                          last edited by

                                          I notice on my 2.5.1 box (I upgraded from 2.4.5 tonight) that after a reboot, if I check unbound, it's only listening on LOCALHOST and not my LAN interface (I have it set to only listen on LAN and LOCALHOST). After a manual restart, it's then listening properly. I've disabled register DHCP leases in DNS for now, and that still doesn't help on a reboot. If my server get's rebooted, my LAN is dead in the water until I can login and restart unbound.

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

                                            @netblues said in DNS randomly stops working:

                                            Service watchdog and unbound don't play well together.

                                            Example good example :

                                            @jasonau said in DNS randomly stops working:

                                            Apr 23 10:15:04 pfsense php[92161]: servicewatchdog_cron.php: The command '/usr/local/sbin/unbound -c /var/unbound/unbound.conf' returned exit code '1', the output was '[1619136904] unbound[68018:0] debug: creating udp4 socket 192.168.1.1 53 [1619136904] unbound[68018:0] error: bind: address already in use [1619136904] unbound[68018:0] fatal error: could not open ports'
                                            Apr 23 10:15:04 pfsense php[73303]: notify_monitor.php: Message sent to XXXXX@hotmail.com OK
                                            Apr 23 10:15:01 pfsense php[92161]: servicewatchdog_cron.php: Service Watchdog detected service unbound stopped. Restarting unbound (DNS Resolver)
                                            

                                            This is probably a perfect example where the Service watchdog cron pfSense package makes the issues worse.
                                            It is 'normal' that the DNS unbound / the resolver is restarted as that this option exactly instructs that to happen :

                                            cc9cb89b-1447-4707-baaa-1179c2cb4f85-image.png

                                            So, it received a restart (a DHCP lease came in) : it stop, and start again : this can be seen in the logs !
                                            The service watchdog sees the process unbound stopping (and doesn't know the difference between dying and stopping) and tries to start an instance of unbound.
                                            But it was already in a restart phase : the instance that was running in the past is just restarting.. Now TWO instances of unbound are trying to compete for a start-up.
                                            The first one - the one that was already running in the past) binds to the port 53 again on all selected interfaces, and the second, started by the service watchdog,sees this ports already in use, and complains. The error log message is now perfectly explained. We can see that there are two unbound processes here : 92161 and 73303 - and the second one logs an error and stops.

                                            People : please, for your own sake : do not make the issue worse.

                                            Unbound can be a light weight process, your device has nothing else to do as starting and stopping processes. But then pfBlockerNG came along, and it could put a "huge block of concrete" around the feeds of unbound. Now, unbound has some difficulties to start 'fast' as it needs to parse thousands of (DNSBL) lines first.
                                            Or : you have thousands of devices on your network and they - as usual, all use DHCP to obtain an IP (lease).
                                            Or : what's also very known now : networks contains device that are very low budget (the gadgets). The use bad behaving code, like DHCP clients that ask a new kease every xx seconds (see the DHCP logs to track them down) : so unbound restarts every xx seconds. So, locate these device and waste bin these devices or better : don't use them, don't buy them.

                                            The Service watchdog cron pfSense can be useful if you have a dying system, and you decided not to invest any time and money into it any more, as it will get replaced asap.
                                            You put a " Service watchdog cron pfSense" on it, an let it start to dig its own hole.

                                            Btw : the person who wrote the Service watchdog (jimp from Netgate) said himself on this forum : Do not use this package - I'm not using it myself. The usage case is very, very rare and only the ones that know how to deal with it should use it.
                                            This excludes 99,99 % of all of us on the forum.

                                            Servers, and other 'always on' devices that are designed to on for days, month or even years do not need such a restart service. Very known programs like bind9, nginx, postfix and also unbound can run for thousands of hours.

                                            IF you can see messages in the logs - the system log and unbound log, where you can see that unbound stops or even "segment faults" or it makes the kernel "dump" - and not starting any more, then, and only then, you could consider using the service watchdog. But in this case, I would take the time to see if this happens often, and if so, going back to the previous version of pfSense.
                                            I did not saw unbound die on me EVER. I do use the amd64 'intel' version.
                                            I know there was an 'arm' compiler issue recently, that could produce a faulty executable. As discussed on the forum.

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

                                            N 1 Reply Last reply Reply Quote 1
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