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    Problemi with dns resolution

    OpenVPN
    dns resolution
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    • S
      sasa1
      last edited by

      Hi,
      I have a problem with a host-to-site, the vpn is working properly but the remote client cannot make a dns resolution.
      After the remote client (Windows 10) is connected in vpn, if I try from a Web browser, to access a website this fails.
      If I use the IP address (and not the domain name) it works.
      In the configuration, in "Advanced Client Settings" in DNS Domain I indicated 8.8.8.8
      Do I need to configure any other parameters?
      Thanks.

      1 Reply Last reply Reply Quote 0
      • KOMK
        KOM
        last edited by

        Did you check the DNS Server enable checkbox?

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        • S
          sasa1
          last edited by

          yes

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          • KOMK
            KOM
            last edited by

            I had to ask. You didn't explicitly say, and I never assume the obvious. I have a similar config and it works for me. If the client runs:

            ipconfig /all
            

            what is showing for DNS servers?

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            • S
              sasa1
              last edited by

              Hi,
              the dns shown is:
              8.8.8.8
              I attach picture.
              Thanks.
              ipconfig.JPG

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              • KOMK
                KOM
                last edited by

                OK, so it seems ot be aware of DNS available to it. Can you ping 8.8.8.8? What happens when you run this on the client:

                nslookup www.microsoft.com
                
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                • S
                  sasa1
                  last edited by

                  the ping is OK, in attached result about dns resolution.
                  Thanks.
                  nslookup1.PNG

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                  • KOMK
                    KOM
                    last edited by

                    Well, there is your problem. Can you ping 8.8.8.8?

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                    • S
                      sasa1
                      last edited by

                      yes, ping to 8.8.8.8 is OK.
                      Thanks.

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                      • KOMK
                        KOM
                        last edited by

                        OK, so what happens when you run:

                        nslookup
                        server 8.8.8.8
                        www.microsoft.com
                        

                        As I recall, on the OpenVPN page there were some mitigation options for Windows 10 clients. Have you tried checking Force DNS cache update under Advanced Client Settings?

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                        • S
                          sasa1
                          last edited by

                          the result is in attach.
                          Yes, force DNS cache update is already selected.nslookup2.PNG
                          Thanks.

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                          • KOMK
                            KOM
                            last edited by

                            Show me a screenshot of your firewall rules for the OpenVPN interface. I suspect you're not allowing UDP traffic or something like that.

                            1 Reply Last reply Reply Quote 0
                            • S
                              sasa1
                              last edited by

                              Hi,
                              attached the required rules.
                              Thanks.rules openvpn.JPG

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                              • KOMK
                                KOM
                                last edited by

                                Set the protocol to Any and try again.

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                                • S
                                  sasa1
                                  last edited by sasa1

                                  Hi,
                                  unfortunately even with any dns resolution it fails.
                                  Thanks.
                                  rules2.JPG

                                  1 Reply Last reply Reply Quote 0
                                  • KOMK
                                    KOM
                                    last edited by

                                    Very strange. Does your firewall log show any relevant blocks while you're testing?

                                    1 Reply Last reply Reply Quote 0
                                    • S
                                      sasa1
                                      last edited by

                                      Hi,
                                      no, I don't see deny in the logs.
                                      Thanks.

                                      1 Reply Last reply Reply Quote 0
                                      • KOMK
                                        KOM
                                        last edited by

                                        Yo @johnpoz Johnny joe ray bob, any thoughts?

                                        1 Reply Last reply Reply Quote 0
                                        • M
                                          marvosa
                                          last edited by marvosa

                                          We need more details on the setup. For clarity, is "host-to-site" referring to a remote access, road warrior setup? If so, post the server1.conf (/var/etc/openvpn).

                                          We'll know more once we see the config, but is all traffic forced thru the tunnel?

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                                          • S
                                            sasa1
                                            last edited by

                                            Hi, attached server1.conf.
                                            The address:
                                            192.168.1.1
                                            is the address of the router / dns referenced by the remote client that connects to my openvpn server.
                                            The pfSense version is 2.3.2, do I need to update it?
                                            Thanks.
                                            server1.txt

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