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    All DNS lookups extremely slow

    Scheduled Pinned Locked Moved General pfSense Questions
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @rollin1
      last edited by

      @rollin1 said in All DNS lookups extremely slow:

      DNSSEC Support enabled and Enable Forward Mode also checked

      That is not a good setting - if your going to forward, dnssec should be off. Where you forward is either doing dnssec or they are not. That setting is going to be nothing but problematic.

      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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      • J
        jrey @rollin1
        last edited by

        @rollin1

        "DNSSEC Support" I assume your upstream supports this and that it is not a new change. You should likely not need this.

        "Enable Forward Mode"
        How is your ping time to your upstream DNS?
        also a traceroute?

        What other packages?
        VPN ? is the upstream DNS on the other end of the VPN?

        What kind of response time are you getting from say
        Diagnostics - > DNS Lookup
        then compare to a dig from the command line (but lookup a different site)

        Then try a nslookup or dig or other (as appropriate) from some connected client?

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator @rollin1
          last edited by johnpoz

          @rollin1 here don't just believe us..

          https://docs.quad9.net/Quad9_For_Organizations/DNS_Forwarder_Best_Practices/

          Disable DNSSEC Validation

          Since Quad9 already performs DNSSEC validation, DNSSEC being enabled in the forwarder will cause a duplication of the DNSSEC process, significantly reducing performance and potentially causing false BOGUS responses.

          edit: side note, 2.6 is no longer supported you should really look to updating. 2.7.2 is the current CE release.

          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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          • R
            rollin1 @johnpoz
            last edited by rollin1

            @johnpoz
            I know i definitely need to upgrade this place.

            @jrey
            Ping times to both DNS servers is 3-4ms. I also disabled DNSSEC. No additional packages are installed. DNS lookups are slow with 127.0.0.1 initially and then its 0ms once the site is cached.

            I also selected the specific interfaces LAN and localhost under DNS Resolver. I selected WAN under Outgoing Network Interfaces. I unchecked Enable DNSSEC Support and Enable Forwarding Mode. Under advanced resolver options I have prefetch DNS Key Support checked and Harden DNSSEC Data checked. I removed the check for Harden before rebooting the pfsense vm.

            I am definitely planning to get the upgrade taken care of this evening.

            Thanks for the help

            johnpozJ 1 Reply Last reply Reply Quote 0
            • johnpozJ
              johnpoz LAYER 8 Global Moderator @rollin1
              last edited by johnpoz

              @rollin1 said in All DNS lookups extremely slow:

              I have prefetch DNS Key Support checked and Harden DNSSEC Data checked.

              Why would you think you need dnssec stuff if your not doing dnssec.. Those could also be removed. But I don't that would a problem - but there is little point to having anything on for dnssec, if your not doing dnssec.

              What do you think is a long time for a response for asking for something? If you forward to something say googledns just example and they don't have what your asking for, they have to resolve it.. So your saying your only 3-4 ms away from where your forwarding? Are these your isp nameservers?

              or do you live down the street from a google data center if your using google ;)

              Here is a query to something I normally don't go too.. This was resolved by unbound, I do not forward.

              ; <<>> DiG 9.16.45 <<>> www.cnn.com @192.168.9.253                     
              ;; global options: +cmd                                                
              ;; Got answer:                                                         
              ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1355               
              ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1   
                                                                                     
              ;; OPT PSEUDOSECTION:                                                  
              ; EDNS: version: 0, flags:; udp: 4096                                  
              ;; QUESTION SECTION:                                                   
              ;www.cnn.com.                   IN      A                              
                                                                                     
              ;; ANSWER SECTION:                                                     
              www.cnn.com.            3600    IN      CNAME   cnn-tls.map.fastly.net.
              cnn-tls.map.fastly.net. 3600    IN      A       146.75.79.5            
                                                                                     
              ;; Query time: 59 msec                                                 
              ;; SERVER: 192.168.9.253#53(192.168.9.253)                             
              ;; WHEN: Wed Dec 13 16:06:04 Central Standard Time 2023                
              ;; MSG SIZE  rcvd: 92                                                  
              

              So a whole 59ms.. that is 0.059 of a second..

              Now sure once I have cached that answer its lower..

              ; <<>> DiG 9.16.45 <<>> www.cnn.com @192.168.9.253
              ;; global options: +cmd
              ;; Got answer:
              ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 23739
              ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1
              
              ;; OPT PSEUDOSECTION:
              ; EDNS: version: 0, flags:; udp: 4096
              ;; QUESTION SECTION:
              ;www.cnn.com.                   IN      A
              
              ;; ANSWER SECTION:
              www.cnn.com.            3523    IN      CNAME   cnn-tls.map.fastly.net.
              cnn-tls.map.fastly.net. 3523    IN      A       146.75.79.5
              
              ;; Query time: 1 msec
              ;; SERVER: 192.168.9.253#53(192.168.9.253)
              ;; WHEN: Wed Dec 13 16:07:21 Central Standard Time 2023
              ;; MSG SIZE  rcvd: 92
              

              Now if you were getting responses that took say 2000 ms or 2 seconds.. I would say you have a problem but even low hundred your talking say like 0.3 seconds for 300 ms..

              Here is asking googledns directly

              ; <<>> DiG 9.16.45 <<>> www.cnn.com @8.8.8.8                                            
              ;; global options: +cmd                                                                 
              ;; Got answer:                                                                          
              ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 51779                               
              ;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 1                    
                                                                                                      
              ;; OPT PSEUDOSECTION:                                                                   
              ; EDNS: version: 0, flags:; udp: 512                                                    
              ;; QUESTION SECTION:                                                                    
              ;www.cnn.com.                   IN      A                                               
                                                                                                      
              ;; ANSWER SECTION:                                                                      
              www.cnn.com.            227     IN      CNAME   cnn-tls.map.fastly.net.                 
              cnn-tls.map.fastly.net. 29      IN      A       151.101.3.5                             
              cnn-tls.map.fastly.net. 29      IN      A       151.101.67.5                            
              cnn-tls.map.fastly.net. 29      IN      A       151.101.131.5                           
              cnn-tls.map.fastly.net. 29      IN      A       151.101.195.5                           
                                                                                                      
              ;; Query time: 20 msec                                                                  
              ;; SERVER: 8.8.8.8#53(8.8.8.8)                                                          
              ;; WHEN: Wed Dec 13 16:11:23 Central Standard Time 2023                                 
              ;; MSG SIZE  rcvd: 140                                                                  
              

              Wow 0.04 of seconds faster, but look at the TTL, so now I have to go ask them again in 30 seconds.. or at best 227 seconds.. Which then again will be most likely some other random ttl lower than what the authoritative ns is.. So save .04 seconds, but will be doing more dns queries... Users do have their reasons for forwarding, hey on a real shitty high latency connection forwarding might be a better solution.. But I find it better to directly talk to the authoritative ns..

              But lets see these queries that are so painfully slow ;)

              Also are you forwarding just via normal forwarding in the clear, or are you forwarding via tls, ie dot?

              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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              • R
                rollin1
                last edited by rollin1

                I changed their configuration yesterday after the suggestions on here

                DNS Resolver is enabled
                I decided to no longer Forward

                Advanced Settings
                Increased Message Cache to 250MB
                Increased Number of hosts to cache to 200000

                Lookup Response Times
                domain 1
                1st lookup
                127.0.0.1 30 msec
                8.8.8.8 53 msec
                8.8.4.4 3 msec

                2nd lookup
                127.0.0.1 0 msec
                8.8.8.8 52 msec
                8.8.4.4 3 msec

                domain 2
                1st lookup
                127.0.0.1 43 msec
                8.8.8.8 14 msec
                8.8.4.4 4 msec

                2nd lookup
                127.0.0.1 0 msec
                8.8.8.8 13 msec
                8.8.4.4 3 msec

                The domain can be cached in pfSense but from any workstation or server on the LAN its a 5-10 second delay before anything is displayed

                johnpozJ 1 Reply Last reply Reply Quote 0
                • johnpozJ
                  johnpoz LAYER 8 Global Moderator @rollin1
                  last edited by

                  @rollin1 So that a lan client doing those looks you posted? Once it is cached in unbound - the client should get a response in 1 or 2ms tops.. Or you have something on on your network between the client and pfsense.

                  Lets say 500 ms even for a dns query does not equate to a website taking 5-10 to display? What browser are you using? You sure its even using your local dns and not doh?

                  Fire up say in firefox the web developers tools and you can see exactly something takes or what is delay.. Sure chrome or edge has sim tools?

                  Are you blocking stuff and it keeps trying a retrans before it gives up?

                  5 to 10 seconds for something to load doesn't seem like slow dns to me - you got something else going on..

                  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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                  • R
                    rollin1 @johnpoz
                    last edited by

                    @johnpoz
                    So that a lan client doing those looks you posted?
                    This is a lan workstation, logged into pfsense via web gui using Diagnostics - DNS Lookup
                    Once it is cached in unbound - the client should get a response in 1 or 2ms tops - I completely agree with you

                    Or you have something on on your network between the client and pfsense.
                    I don't have anything between the client and pfsense.

                    Lets say 500 ms even for a dns query does not equate to a website taking 5-10 to display?
                    I am not saying that it translates I was really trying to review everything and hopefully with other users have more pfsense configuration experience than myself

                    What browser are you using?
                    I have used all of them - Chrome, Firefox, Edge

                    You sure its even using your local dns and not doh?
                    I have pointed clients to local dns servers and to google dns servers and the issue still exists either way

                    Fire up say in firefox the web developers tools and you can see exactly something takes or what is delay.. Sure chrome or edge has sim tools?
                    I will also check into this tonight/tomorrow morning using Firefox web developer tools

                    Are you blocking stuff and it keeps trying a retrans before it gives up?
                    No filtering or blocking is being done
                    No VPN's configured

                    5 to 10 seconds for something to load doesn't seem like slow dns to me - you got something else going on..
                    I also patched the clients 2nd ESXi host today. Afterword, I deployed a fresh install of PFSense and I updated 2.6.0 to 2.7.0 successfully running a copy of clients config. The production pfsense vm is running on a host that needs ESXi to be patched, so pfsense 2.7.0 and newer will run properly.

                    johnpozJ 1 Reply Last reply Reply Quote 0
                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator @rollin1
                      last edited by johnpoz

                      @rollin1 said in All DNS lookups extremely slow:

                      I have pointed clients to local dns servers and to google dns servers and the issue still exists either way

                      Browsers these days like to ignore your client settings and use doh anyway, unless you jump through hoops to disable the use of doh.

                      But if it is using what you set in the client, and you pointed it directly to say googledns and still slow, kind of points to something other than dns being the source of the slow page load.

                      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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                      • J
                        jrey @johnpoz
                        last edited by

                        @johnpoz said in All DNS lookups extremely slow:

                        pointed clients to local dns servers and to google dns servers

                        clients local dns AND google

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @jrey
                          last edited by

                          @jrey said in All DNS lookups extremely slow:

                          clients local dns AND google

                          This is never a good setup anyway - since you really have no idea exactly which the client will use when you point to more than one NS.

                          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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                          • J
                            jrey @johnpoz
                            last edited by

                            @johnpoz

                            This is never a good setup anyway

                            that was my point.

                            I, like you, would much rather see the actual "dig" or "NSLookup" directly from whatever the client is, not just the times. just the times doesn't really say what the response was or if there even was a valid response. Without knowing what "domain 1" or "domain 2" are or what might be actually loading (a webpage? something else?)

                            This really does not feel like a DNS "slowness" issue.

                            you got something else going on

                            ^^ yup

                            after the suggestions on here
                            ..
                            increased Message Cache to 250MB
                            Increased Number of hosts to cache to 200000

                            did I miss something on here?

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

                              nslookup will use what 'system' (PC) uses.
                              An application like Firefox, out of the box, will completely bypass the system DNS, and goes directly to the outside DoH server, doing its DoH thing. The pfSense resolver will never see the requests.

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

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                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator @jrey
                                last edited by

                                @jrey said in All DNS lookups extremely slow:

                                did I miss something on here?

                                you don't need to adjust those to be honest, the defaults should be fine.. And that sure has nothing to do with whatever issue your having.

                                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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                                • J
                                  jrey @johnpoz
                                  last edited by

                                  @johnpoz

                                  did I miss something on here?

                                  My question was more about the OP stated changing them in reference to something said "on here".

                                  the defaults should be fine

                                  I'm 100% in agreement with this

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                                  • johnpozJ
                                    johnpoz LAYER 8 Global Moderator @jrey
                                    last edited by

                                    @jrey said in All DNS lookups extremely slow:

                                    reference to something said "on here".

                                    No idea where he would of seen that - I have sure never stated anything of the sort. And don't recall any one saying it, if I would of seen it I would of questioned it.

                                    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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                                    • R
                                      rollin1 @johnpoz
                                      last edited by

                                      @johnpoz
                                      The pfsense vm is running 2.6.0 right now and its on ESXi 6.0 which will be updated to the most recent patch for esxi 6.0 this week. The pfsense vm also has the vmxnet3 nic's which I know usually work better than the e1000. I have to get the firmware/bios updated on the host and then I plan to patch. I know the host is running extremely old esxi software but they have to continue to keep 4 NT4 servers running for their manufacturing.

                                      I think the settings I found for adjusting things under Advanced Settings were from another support forum. I mistakenly lumped them with the suggestions I got from this group, sorry about doing that.

                                      Anyone else have any ideas after updating the host and the pfsense version to 2.7.2 so they are running current software

                                      I also changed all of my advanced settings back to the defaults for the DB size and the number of entries in the DB.

                                      johnpozJ 1 Reply Last reply Reply Quote 0
                                      • johnpozJ
                                        johnpoz LAYER 8 Global Moderator @rollin1
                                        last edited by

                                        @rollin1 bumping those settings to those values - you must be handling a shit ton of dns to a bunch of different clients all going to lots of different places ;)

                                        If I had a need for dns that those settings would make sense, prob wouldn't be running it on my router ;) And would have a dedicated NS properly sized for my needs.

                                        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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                                        • R
                                          rollin1 @johnpoz
                                          last edited by rollin1

                                          @johnpoz
                                          Those settings were never something I adjusted in any other pfsense install that I have done but the latency is too significant to not notice. What do you think if I change all the settings to forward vs look everything up? I have honestly wondered through out this whole issue if the problem could be with the vm itself. I mean after the DNSSEC settings were changed the lookup times improved but they are definitely not normal. What do you think about the following steps

                                          1. Update ESXI 6 - Client has been running esxi 6 with no patches for a while
                                            A. Once patched to most recent patch for ESXi 6 I can then deploy a fresh 2.7.2 pfsense vm
                                            B. After patches the new 2.7.2 pfsense vm will actually run and not power off
                                            C. Import the clients config on the new vm and see how everything runs

                                          Does anyone see any issue with doing this? I basically want to rule out anything with the existing pfsense vm and their configuration is very basic (no vpn's, no complex network)

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                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator @rollin1
                                            last edited by

                                            @rollin1 I moved away from running pfsense on esxi many years ago - It did have some advantages, but also drawbacks.. I have seen issues where user having performance issues.. But haven't paid much attention to them since not currently running on esxi.

                                            But isn't esxi 6 eol? Like last year??

                                            Isn't 8 current?

                                            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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