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    DHCP not giving out DNS address

    Scheduled Pinned Locked Moved DHCP and DNS
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    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      It is probably hard-set in windows. You can get a dynamic address with hard-set DNS servers.

      Packet capture the DHCP exchange and see what the DHCP server is actually sending. You will likely find it is exactly what is set in the DHCP server.

      Chattanooga, Tennessee, USA
      A comprehensive network diagram is worth 10,000 words and 15 conference calls.
      DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
      Do Not Chat For Help! NO_WAN_EGRESS(TM)

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      • S
        stewii
        last edited by

        Did the dump with wireshark. Followed this guide https://en.wikiversity.org/wiki/Wireshark/DHCP and do not see anything in there with the DNS server IP address that I am specifying in the DHCP server.

        edit: If this is hard set in windows would my linux/android clients get the dns entry? How would I go about fixing it in windows if it is hard set?

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        • DerelictD
          Derelict LAYER 8 Netgate
          last edited by

          If windows has it hard set remove it from the interface config in windows.

          Chattanooga, Tennessee, USA
          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
          Do Not Chat For Help! NO_WAN_EGRESS(TM)

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by

            Didn't see anything?  How about you post it…

            So show us that you wanting to hand out 192.168.1.10, for example I hand out 192.168.3.10 -- here I did a release and then renew, you can see in the offer 192.168.3.10 was offered..

            dnsviadhcp.png
            dnsviadhcp.png_thumb

            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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            • S
              stewii
              last edited by

              Thanks for pointing out where to look. I changed it to 192.168.1.52 just to try and still receiving 192.168.1.1. See attachments. I think I just realized what you meant by windows hard set. No it is not hard set.

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              • DerelictD
                Derelict LAYER 8 Netgate
                last edited by

                You have another DHCP server on your network. Look at the source MAC address of the DHCP server responses.

                Chattanooga, Tennessee, USA
                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  Or you have a reservation setup for that client.. Your client is 192.168.1.7 but your pool is 150-254 so clearly its not coming from that pool..

                  Notice my pool, my client .100 is outside that pool I have a reservation/static for it set..

                  staticreservation.png
                  staticreservation.png_thumb

                  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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                  • S
                    stewii
                    last edited by

                    Don't have a second DHCP server but I do have a static reservation for the client. Almost all of my clients have a static reservation. So this brings up two questions.

                    1. if I use a DHCP reservation on pfsense how do I send DNS to the client that gets the reservation without hard setting it on the client?

                    2 I have other non windows clients (Sonos and android) that are in the DHCP pool that do not report back to my dns server 192.168.1.52 (remember I changed it). If DHCP is sending out DNS why wouldn't these clients use the DNS that it is supposed to from DHCP?

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      " If DHCP is sending out DNS why wouldn't these clients use the DNS that it is supposed to from DHCP?"

                      because they haven't updated their lease yet??

                      So set the dns you want your client to use in the reservation..  If you don't then yeah its going to get the IP address your dhcp server is running on as default.

                      reservation.png_thumb
                      reservation.png

                      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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                      • S
                        stewii
                        last edited by

                        So after a reboot of pfsense, everything started working as it should. I guess the reboot released all the static leases?

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator
                          last edited by

                          huh?  Or you client updated its lease.. And the reboot had zero to do with 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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                          • S
                            stewii
                            last edited by

                            I guess I should have been more clear. After a reboot of pfsense, all clients started talking to my DNS server as it is configured in pfsense. Meaning all clients windows linux android and whatever sonos runs on(probably linux) started reporting into the DNS server at 192.168.1.52. So take it how you want….

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