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    Windows Clients cannot access the internet, very strange unexpected DNS problem.

    Scheduled Pinned Locked Moved DHCP and DNS
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    • bmeeksB
      bmeeks @IrixOS
      last edited by bmeeks

      @IrixOS
      To amplify what @johnpoz is saying --

      The ACL (access control list) for unbound limits what IP addresses can ask for DNS lookups. Think of it as a type of "firewall" for unbound. pfSense will automatically create ACL entries for unbound to cover all of the directly attached networks. But if you have downstream networks that are not defined directly on pfSense that are attempting to query unbound on pfSense, then you will need to create custom ACL entries to allow that traffic (in addition to pfSense firewall rules that allow those downstream IP addresses past the pfSense firewall).

      I 1 Reply Last reply Reply Quote 0
      • I
        IrixOS @bmeeks
        last edited by

        @bmeeks I just filled in the fields of the ACL, already gone through that, I won't budge. My summary route is 10.216.0.0./17 so I filled in that, disabled the auto-rules.

        Any other ideas?
        Feel free to ask me any question,

        Thank you,

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

          @IrixOS I am not sure if the manual ACLs work, if you have auto acls set... So its quite possible if auto is still enabled and you create your own that it might not be working.. Did you restart unbound after creating the acls?

          A simple directed query would be easier to see if your getting refused, acl not allowing.. or a servfail?

          $ dig @192.168.9.253 www.bing.com
          
          ; <<>> DiG 9.16.48 <<>> @192.168.9.253 www.bing.com
          ; (1 server found)
          ;; global options: +cmd
          ;; Got answer:
          ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55311
          ;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 1
          
          ;; OPT PSEUDOSECTION:
          ; EDNS: version: 0, flags:; udp: 4096
          ;; QUESTION SECTION:
          ;www.bing.com.                  IN      A
          
          ;; ANSWER SECTION:
          www.bing.com.           18539   IN      CNAME   www-www.bing.com.trafficmanager.net.
          www-www.bing.com.trafficmanager.net. 539 IN CNAME www-bing-com.dual-a-0001.a-msedge.net.
          www-bing-com.dual-a-0001.a-msedge.net. 539 IN CNAME dual-a-0001.a-msedge.net.
          dual-a-0001.a-msedge.net. 539   IN      A       13.107.21.200
          dual-a-0001.a-msedge.net. 539   IN      A       204.79.197.200
          
          ;; Query time: 1 msec
          ;; SERVER: 192.168.9.253#53(192.168.9.253)
          ;; WHEN: Mon Feb 26 11:52:32 Central Standard Time 2024
          ;; MSG SIZE  rcvd: 184
          

          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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          • I
            IrixOS @johnpoz
            last edited by

            @johnpoz that IP you are mentioning, is that your clients IP?

            Auto-rules disabled and added 10.217.0.0/17 (summary) to the ACL,

            When doing dig this is the output:

            Dig.jpg

            bmeeksB 1 Reply Last reply Reply Quote 0
            • bmeeksB
              bmeeks @IrixOS
              last edited by

              @IrixOS said in Windows Clients cannot access the internet, very strange unexpected DNS problem.:

              @johnpoz that IP you are mentioning, is that your clients IP?

              Auto-rules disabled and added 10.217.0.0/17 (summary) to the ACL,

              When doing dig this is the output:

              Dig.jpg

              Is that 10.217.0.0/17 the entry you added to the ACL? If so, then by my calculations the IP that is querying (10.216.64.29) is not within that subnet. Is 10.216.64.29 one of the Windows clients?

              johnpozJ I 2 Replies Last reply Reply Quote 0
              • johnpozJ
                johnpoz LAYER 8 Global Moderator @bmeeks
                last edited by johnpoz

                @bmeeks

                Yeah 10.217/17 would be 10.217.0.0 - 10.217.127.255, so you are correct 10.216.64.x would not be allowed.

                But that error looks like firewall rule with a reject or something, not unbound acl refusing you.. which would look like this..

                Here I temp removed 192.168/16 from my ACL, and then did a query..

                acl.jpg

                Your getting an error that you couldn't even talk to 64.29, and from your sniff thought your dns your .29 client was asking was .18..

                In that command your asking 64.29, isn't that your windows client? So yeah I would expect him not to answer a dns query.

                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

                bmeeksB I 3 Replies Last reply Reply Quote 0
                • bmeeksB
                  bmeeks @johnpoz
                  last edited by bmeeks

                  @johnpoz:
                  Duh! You are correct. I didn't even notice he appears to have run the DNS query from a pfSense session (if the 10.216.64.29 client is in fact a Windows machine).

                  @IrixOS:
                  Now, if the 10.216.64.29 Windows target is a Microsoft AD Controller/DNS server, then you also may have an issue with the Windows firewall on the server. It will automatically drop inbound traffic that is not from the local subnet (if the firewall is enabled, which it is ON by default in Windows these days). I don't think you can fully troubleshoot your problem at the pfSense firewall. You need to run a DNS query via nslookup or dig from a client on the network where you are having DNS problems. The returned error code will then be the clue to the real problem.

                  By the way, since the default pfSense firewall rules allow the firewall to go anywhere, that "connection refused" message is likely coming from the target device (the 10.216.64.29 machine). I would initially suspect a local firewall to be the cause of the refused connection.

                  1 Reply Last reply Reply Quote 0
                  • I
                    IrixOS @bmeeks
                    last edited by

                    @bmeeks Yes 10.216.64.29 is the ip address of the client, the Local Route (L) in routing table is the /30 subnet 10.216.64.29-10.216.64.30 and this subnet is advertised into ospf.

                    Pardon me, it is 10.216.0.0/17 not 217 (summary route of al internal ospf routes) is in the ACL and that didn't work.

                    johnpozJ bmeeksB 2 Replies Last reply Reply Quote 0
                    • I
                      IrixOS @johnpoz
                      last edited by

                      @johnpoz Sorry my mistake it is 10.216.0.0/17 I configured in the ACL, didn't work, wireshark outputs the error.

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

                        @IrixOS well you still did a query to .29 which no I wouldn't expect that to answer unless you were running dns on it.

                        lets see s basic nslookup from this windows client.

                        And then you could put it into debug mode to get more info..

                        Here

                        $ nslookup                                                                                             
                        Default Server:  sg4860.home.arpa                                                             
                        Address:  192.168.9.253                                                                       
                                                                                                                      
                        > www.bing.com                                                                                
                        Server:  sg4860.home.arpa                                                                     
                        Address:  192.168.9.253                                                                       
                                                                                                                      
                        Non-authoritative answer:                                                                     
                        Name:    dual-a-0001.a-msedge.net                                                             
                        Addresses:  13.107.21.200                                                                     
                                  204.79.197.200                                                                      
                        Aliases:  www.bing.com                                                                        
                                  www-www.bing.com.trafficmanager.net                                                 
                                  www-bing-com.dual-a-0001.a-msedge.net                                               
                                                                                                                      
                        > set debug                                                                                   
                        > www.bing.com                                                                                
                        Server:  sg4860.home.arpa                                                                     
                        Address:  192.168.9.253                                                                       
                                                                                                                      
                        ------------                                                                                  
                        Got answer:                                                                                   
                            HEADER:                                                                                   
                                opcode = QUERY, id = 7, rcode = NXDOMAIN                                              
                                header flags:  response, auth. answer, want recursion, recursion avail.               
                                questions = 1,  answers = 0,  authority records = 0,  additional = 0                  
                                                                                                                      
                            QUESTIONS:                                                                                
                                www.bing.com.home.arpa, type = A, class = IN                                          
                                                                                                                      
                        ------------                                                                                  
                        ------------                                                                                  
                        Got answer:                                                                                   
                            HEADER:                                                                                   
                                opcode = QUERY, id = 8, rcode = NXDOMAIN                                              
                                header flags:  response, auth. answer, want recursion, recursion avail.               
                                questions = 1,  answers = 0,  authority records = 0,  additional = 0                  
                                                                                                                      
                            QUESTIONS:                                                                                
                                www.bing.com.home.arpa, type = AAAA, class = IN                                       
                                                                                                                      
                        ------------                                                                                  
                        ------------                                                                                  
                        Got answer:                                                                                   
                            HEADER:                                                                                   
                                opcode = QUERY, id = 9, rcode = NOERROR                                               
                                header flags:  response, want recursion, recursion avail.                             
                                questions = 1,  answers = 5,  authority records = 0,  additional = 0                  
                                                                                                                      
                            QUESTIONS:                                                                                
                                www.bing.com, type = A, class = IN                                                    
                            ANSWERS:                                                                                  
                            ->  www.bing.com                                                                          
                                canonical name = www-www.bing.com.trafficmanager.net                                  
                                ttl = 16365 (4 hours 32 mins 45 secs)                                                 
                            ->  www-www.bing.com.trafficmanager.net                                                   
                                canonical name = www-bing-com.dual-a-0001.a-msedge.net                                
                                ttl = 1665 (27 mins 45 secs)                                                          
                            ->  www-bing-com.dual-a-0001.a-msedge.net                                                 
                                canonical name = dual-a-0001.a-msedge.net                                             
                                ttl = 1665 (27 mins 45 secs)                                                          
                            ->  dual-a-0001.a-msedge.net                                                              
                                internet address = 13.107.21.200                                                      
                                ttl = 1665 (27 mins 45 secs)                                                          
                            ->  dual-a-0001.a-msedge.net                                                              
                                internet address = 204.79.197.200                                                     
                                ttl = 1665 (27 mins 45 secs)                                                          
                                                                                                                      
                        ------------                                                                                  
                        Non-authoritative answer:                                                                     
                        ------------                                                                                  
                        Got answer:                                                                                   
                            HEADER:                                                                                   
                                opcode = QUERY, id = 10, rcode = SERVFAIL                                             
                                header flags:  response, want recursion, recursion avail.                             
                                questions = 1,  answers = 0,  authority records = 0,  additional = 0                  
                                                                                                                      
                            QUESTIONS:                                                                                
                                www.bing.com, type = AAAA, class = IN                                                 
                                                                                                                      
                        ------------                                                                                  
                        Name:    dual-a-0001.a-msedge.net                                                             
                        Addresses:  13.107.21.200                                                                     
                                  204.79.197.200                                                                      
                        Aliases:  www.bing.com                                                                        
                                  www-www.bing.com.trafficmanager.net                                                 
                                  www-bing-com.dual-a-0001.a-msedge.net                                               
                                                                                                                      
                        >
                        

                        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

                        I 1 Reply Last reply Reply Quote 1
                        • bmeeksB
                          bmeeks @IrixOS
                          last edited by

                          @IrixOS:
                          The next step in my opinion is to attempt an nslookup or dig query from one of the impacted clients. You can't run the dig command from the pfSense box and target that Windows machine. Unless that Windows machine is a DNS server, it will never respond to the query.

                          Edit: see @johnpoz beat me posting a reply by a few seconds...

                          1 Reply Last reply Reply Quote 0
                          • I
                            IrixOS @johnpoz
                            last edited by IrixOS

                            @johnpoz I created a rule, might be wrong don't know.

                            NAT.jpg Rule.jpg

                            Is this correct?

                            johnpozJ 1 Reply Last reply Reply Quote 0
                            • I
                              IrixOS @johnpoz
                              last edited by

                              @johnpoz Dig_1.jpg Dig_2.jpg

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

                                @IrixOS yeah your rule on your lan looks right to allow any traffic from a downstream network on 10.216/17.. But that outbound looks wrong.. Why would you have a "modem" interface, is this not pfsense wan? What would 172.16 have to do with dns working if you ask pfsense IP?

                                Be it your device is natted to get to the internet has little to do with some client behind pfsense asking it for dns, that dns would resolve..

                                If you go to dns lookup under diagnostics and put in www.bing.com what do you get?

                                dns.jpg

                                Why are you in manual for outbound nat? When you create a gateway in pfsense, and then create routes to that gateway.. Pfsense would automatically add those outbound nat rules to allow these downstream networks to be natted to pfsense wan IP.. I have no idea what your modem interface is, and how that would have to do with getting to the internet, because your only going to be natting to destinations in that 172.16.1/24 to whatever that modem interface IP is on pfsense.. Not sure how that gets a client to the internet? Client trying to get to the internet say 8.8.8.8 would not be 172.16.1 for destination.. So you wouldn't be natting anything..

                                Well can tell you right now you have something wrong with unbound, because your not even returning the ptr for pfsense own IP... Which would always be a given.. So either 192.168.1.1 is not pfsense? Or its dns is borked.. because it wold always return the IP of the name you setup for pfsense.. Is that 192.168.1.1 not pfsense lan IP?

                                What is this 192.168.1.1 address.. You would think you would point your clients to pfsense IP on your transit network?

                                Is that 192.168.1.1 address is a pfsense other IP and you want to query it for dns, you should prob setup a host override for it.. etc..

                                example, here I changed server in nslookup to use a different IP of pfsense.

                                > server 192.168.3.253
                                ------------
                                Got answer:
                                    HEADER:
                                        opcode = QUERY, id = 11, rcode = NOERROR
                                        header flags:  response, auth. answer, want recursion, recursion avail.
                                        questions = 1,  answers = 1,  authority records = 0,  additional = 0
                                
                                    QUESTIONS:
                                        253.3.168.192.in-addr.arpa, type = PTR, class = IN
                                    ANSWERS:
                                    ->  253.3.168.192.in-addr.arpa
                                        name = sg4860.dmz.home.arpa
                                        ttl = 3600 (1 hour)
                                
                                ------------
                                Default Server:  sg4860.dmz.home.arpa
                                Address:  192.168.3.253
                                

                                See how it returns slightly different name, 192.168.3 I call my dmz segment.. But a client should always be able to resolve stuff you have local on pfsense, like pfsense name.. if it can't then you got something really wrong..

                                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

                                I 1 Reply Last reply Reply Quote 1
                                • bmeeksB
                                  bmeeks @IrixOS
                                  last edited by bmeeks

                                  @IrixOS:
                                  I agree with @johnpoz and don't understand the purpose of the manual outbound NAT rule going to the Modem Address (and with that 172.16.x.x destination). You can tell by the little globe icon on the right side of the Windows client's Task Bar that it does not have Internet access. That globe icon means "no Internet". It will be a little square box looking icon when the client can ping a certain Microsoft address.

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                                  • I
                                    IrixOS @johnpoz
                                    last edited by

                                    @johnpoz Ah I thought you knew, the pfsense is connected with a VDSL modem which is in bridged mode. According to the handbook this NAT rule is necessary, please correct me?

                                    johnpozJ 1 Reply Last reply Reply Quote 0
                                    • I
                                      IrixOS @bmeeks
                                      last edited by

                                      @bmeeks Yes I desperately waiting for that square on the taskbar to appear,...

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

                                        @IrixOS not that rule should not be necessary... If you take some device and connect it to pfsense, be it you bridge a public IP to pfsense or whatever.. That would still be pfsense wan..

                                        While I don't have a lot of experience with however you seem to be setup for a "modem" that rule makes zero sense at all.. As I stated why would you nat your clients to some "modem" interface... Isn't your device connect to pfsense wan? And your only going to nat traffic dest for that 172.16 network... Which would be why.. If you maybe want to connect to its web gui? But that would have zero to do with internet access for your clients..

                                        And you have it setup where pfsense can not even do dns, that would also explain your servfail responses... What does dns lookup on pfsense show for www.bing.com - per my example above.

                                        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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                                        • I
                                          IrixOS @johnpoz
                                          last edited by

                                          @johnpoz dnslookup.jpg

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

                                            @IrixOS well yeah then dns is never going to work.. if pfsense itself can not look up www.bing.com, how would you expect a client asking it to lookup www.bing.com would get an answer..

                                            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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