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    Wrong DHCP subnet

    Scheduled Pinned Locked Moved DHCP and DNS
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    • K
      kdi.isusovci
      last edited by

      Hello,

      I have a problem with clients with cable connected. We have a house with cca 100 patch cable installation.

      Few days ago, I setup pfSense with DHCP on LAN as 10.100.100.50-250 and some PCs receive IP from different subnet as 10.10.0.x. Why is that happening?

      We have two 42-port switches and both are managed and set to 10.100.100.5 and 6 as IP and 10.100.100.2 as gateway.

      Why is that happening and how can I find the result of this? Thank you very much for your help!

      Ivan

      NogBadTheBadN 1 Reply Last reply Reply Quote 0
      • NogBadTheBadN
        NogBadTheBad @kdi.isusovci
        last edited by

        @kdi-isusovci

        Do an ipconfig /all and look what IP address is handing out the wrong subnet.

        Andy

        1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

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

          So you setup pfsense as 10.100.100.2/ 24 as its IP??

          Or did you use say a different mask than /24 so dhcp could be larger? like /8 (255.0.0.0)

          If you truely setup pfsense on 10.100.100/24 then its not possible that pfsense would hand out that IP range - and you have another dhcp server on your network.

          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 2.7.2, 24.11

          K 1 Reply Last reply Reply Quote 0
          • K
            kdi.isusovci @johnpoz
            last edited by

            @johnpoz I setup pfsense as 10.100.100.2 /24

            @NogBadTheBad i recieve something like this:

            IP: 10.10.0.213
            mask: 255.255.255.0
            GW: 10.10.0.1

            and that doesn't exist.

            1 Reply Last reply Reply Quote 0
            • K
              kdi.isusovci
              last edited by

              Sorry, I found the solution. It was one of AP's that I accidentally typo, I setup it's IP as 10.100.0.12 and I needed 10.100.100.12, and also it was DHCP turned on.

              Is there any solution to stop users to connect their AP's and setup it without me? It shows that all internet can crash cuz of that.

              Thanks!

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

                You have users connecting rouge AP to your network? Yeah to stop that you would need to use a NAC be it by hand or automatic, etc.

                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 2.7.2, 24.11

                1 Reply Last reply Reply Quote 0
                • JKnottJ
                  JKnott @kdi.isusovci
                  last edited by

                  @kdi-isusovci said in Wrong DHCP subnet:

                  Sorry, I found the solution. It was one of AP's that I accidentally typo, I setup it's IP as 10.100.0.12 and I needed 10.100.100.12, and also it was DHCP turned on.

                  Is there any solution to stop users to connect their AP's and setup it without me? It shows that all internet can crash cuz of that.

                  Thanks!

                  Some managed switches will allow only specified MAC addresses on each port.

                  PfSense running on Qotom mini PC
                  i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                  UniFi AC-Lite access point

                  I haven't lost my mind. It's around here...somewhere...

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