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    DNS issue while connected to OpenVPN

    Scheduled Pinned Locked Moved OpenVPN
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    • jimpJ
      jimp Rebel Alliance Developer Netgate
      last edited by

      When you exported the configuration for Windows clients, did you check the Block Outside DNS option?

      Though the option that enables should only be relevant on Windows 10.

      It adds this to the OpenVPN configuration:

      setenv opt block-outside-dns
      

      Also make sure that the DNS resolver is configured with an ACL to allow the OpenVPN client subnet to make DNS queries.

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      • A
        albertmiclat
        last edited by

        Hi Jimp,

        When you exported the configuration for Windows clients, did you check the Block Outside DNS option? Nope i didn't tick this option when i export the Windows client configuration.

        will this work if tick only on the OpenVPN server? or the Windows client export must also have?

        Also make sure that the DNS resolver is configured with an ACL to allow the OpenVPN client subnet to make DNS queries. where can i check this?

        Thanks,
        A

        jimpJ 1 Reply Last reply Reply Quote 0
        • jimpJ
          jimp Rebel Alliance Developer Netgate @albertmiclat
          last edited by

          @albertmiclat said in DNS issue while connected to OpenVPN:

          will this work if tick only on the OpenVPN server? or the Windows client export must also have?

          That is not a server-side option. It only works on Windows clients so it would go in the Windows client configuration.

          Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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          • A
            albertmiclat
            last edited by

            @jimp
            That is not a server-side option. It only works on Windows clients so it would go in the Windows client configuration. i noticed on the server configuration this option is also visible.
            4f41421c-8af6-425f-b196-6483ad4a36a1-image.png

            Also make sure that the DNS resolver is configured with an ACL to allow the OpenVPN client subnet to make DNS queries. where can i check this?

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            • jimpJ
              jimp Rebel Alliance Developer Netgate
              last edited by

              Yes, but it pushes that to the client, it doesn't affect how the server behaves.

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              • A
                albertmiclat
                last edited by

                @jimp
                Ok, so if i want this setting to be active i must export a new Windows client configuration correct?

                by default DNS resolver is enabled, im not sure where the ACL where can i check this?
                39664538-b62c-455d-b681-23fcf228dc1c-image.png

                thanks

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                • jimpJ
                  jimp Rebel Alliance Developer Netgate
                  last edited by

                  That wouldn't affect VPN clients in any way, only the firewall itself.

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                  • A
                    albertmiclat
                    last edited by

                    Ok..

                    Also make sure that the DNS resolver is configured with an ACL to allow the OpenVPN client subnet to make DNS queries. how can i check this settings?

                    thanks

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                    • jimpJ
                      jimp Rebel Alliance Developer Netgate
                      last edited by

                      Services > DNS Resolver, Access Lists tab

                      Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                      • noplanN
                        noplan
                        last edited by

                        do you use the netBios setting ?
                        out of the blue
                        brNP

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                        • A
                          albertmiclat @noplan
                          last edited by

                          @noplan if you are referring to this? then yes
                          0bb43550-5432-4794-b73c-4adb41933907-image.png

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                          • A
                            albertmiclat @jimp
                            last edited by

                            @jimp looks like DNS resolver is not enabled, can i still proceed to add the ACL or this must be enable first?
                            2b932d0d-b61c-430f-9953-12e0a361fb3a-image.png

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                            • jimpJ
                              jimp Rebel Alliance Developer Netgate
                              last edited by

                              Are you using the DNS Forwarder then?

                              Or what are the clients using for DNS if not the firewall?

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                              • A
                                albertmiclat @jimp
                                last edited by

                                @jimp DNS forwarders also not enabled.

                                our clients is using our Windows DNS servers..

                                configured on here System > General Setting
                                cb552701-a081-4d6e-b5e3-0fb1fe5aeb22-image.png

                                and here for OpenVPN
                                4bb91fb3-91a8-460c-abee-85ce44a1d883-image.png

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                                • jimpJ
                                  jimp Rebel Alliance Developer Netgate
                                  last edited by

                                  OK so the firewall would not be involved in their DNS at all. The "Block outside DNS" box is about all you can do there other than trying to solve client issues.

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                                  • A
                                    albertmiclat @jimp
                                    last edited by

                                    @jimp Ok.

                                    so for the "Block outside DNS" i need to generated a new Windows client configuration with "Block outside DNS" tick to get this setting in effect?

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                                    • jimpJ
                                      jimp Rebel Alliance Developer Netgate
                                      last edited by

                                      You can check the box on the server which may help. If it doesn't, then try exporting a fresh client.

                                      If neither one helps then it's something else entirely, most likely not in OpenVPN. Could be on the client or the DNS server, but either way, not pfSense and unlikely to be OpenVPN.

                                      Remember: Upvote with the ๐Ÿ‘ button for any user/post you find to be helpful, informative, or deserving of recognition!

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                                      • A
                                        albertmiclat @jimp
                                        last edited by

                                        @jimp Thanks jimp.. I will do some testing first. Thanks!

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                                        • A
                                          albertmiclat
                                          last edited by

                                          @jimp base on my testing the user still encounter the same problem unable to resolves DNS hostname.

                                          my openvpn subnet is 10.50.0.0/22, i noticed when the user is getting 10.50.1.X ip address they encounter the DNS issue.

                                          i dont have any clue where to check next, any advice will be greatly appreciated. Thanks

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

                                            @albertmiclat said in DNS issue while connected to OpenVPN:

                                            the user is getting 10.50.1.X ip address

                                            Ok for the IP, but what about the IP of the DNS the client received ? Why not mentionning it ? The gateway and mask while you're at it.
                                            The DNS IP is your DNS server in your/a network ? Can it be accessed by the OpenVPN client ? Is the DNS set up to receive DNS requests from OpenVPN clients ?
                                            Note : You're not using pfSense as a DNS for your networks, but some other device. So pfSense OpenVPN server should be set up accordingly. How ? depends on your network ....

                                            I guess you should use :

                                            8ec8feee-860a-4759-8fa3-3b246ae7084a-image.png

                                            where a.b.c.d is your DNS.

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

                                            A 1 Reply Last reply Reply Quote 1
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