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    Bizarre IP in my LAN

    Scheduled Pinned Locked Moved DHCP and DNS
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    • AndyRHA
      AndyRH @Modesty
      last edited by

      @Modesty Rouge DHCP server? Do a packet capture on a client and force an IP renew. If there is a rouge you will see it in the packet capture.

      o||||o
      7100-1u

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

        @Modesty yup packet capture would do it, or you could use nmap

        $ nmap --script broadcast-dhcp-discover -e eth1
        Starting Nmap 7.95 ( https://nmap.org ) at 2024-11-14 08:21 Central Standard Time
        Pre-scan script results:
        | broadcast-dhcp-discover:
        |   Response 1 of 1:
        |     Interface: eth1
        |     IP Offered: 192.168.9.110
        |     DHCP Message Type: DHCPOFFER
        |     Server Identifier: 192.168.9.253
        |     IP Address Lease Time: 4d00h00m00s
        |     WPAD:
        |
        |     Subnet Mask: 255.255.255.0
        |     Router: 192.168.9.253
        |     Domain Name Server: 192.168.3.10
        |     Domain Name: home.arpa
        |     NTP Servers: 192.168.3.32
        |_    NetBIOS Node Type: 1
        WARNING: No targets were specified, so 0 hosts scanned.
        Nmap done: 0 IP addresses (0 hosts up) scanned in 10.10 seconds
        

        Yes nmap can run on windows ;) Or MS even put out a tool back in the day.. Old technet article - but that is long gone - but you can grab it from here

        https://tachytelic.net/2019/05/detect-rogue-dhcp-server/

        Still works on windows 10

        dhcp.jpg

        Its only finding my actual dhcp server, pfsense.. But if there is more than 1 on your network you should discover 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

        AndyRHA 1 Reply Last reply Reply Quote 0
        • M
          Modesty
          last edited by Modesty

          WOW

          I used Rougue Checker and found

          086c80fc-c477-4ea6-aad2-1758dfb29385-image.png

          4263e5a8-1ddc-4827-9bcb-de308c73715a-image.png

          Is the 169.254.5.254 on my PC? Its not on my pfSense box

          Any tip to help me one more step?

          Everything can be rebuilt!

          johnpozJ 1 Reply Last reply Reply Quote 0
          • AndyRHA
            AndyRH @johnpoz
            last edited by

            @johnpoz said in Bizarre IP in my LAN:

            or you could use nmap

            Nuts, did not think about that.

            o||||o
            7100-1u

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

              @Modesty said in Bizarre IP in my LAN:

              169.254.5.254

              That is a link-local IPv4 address, also known as APIPA - windows will give itself that address when an interface is set for dhcp, but a dhcp server does not answer.. No you really shouldn't have that IP on your PC..

              What doe the output of ipconfig /all show?

              example

              Windows IP Configuration                                                                       
                                                                                                             
                 Host Name . . . . . . . . . . . . : i9-win                                                  
                 Primary Dns Suffix  . . . . . . . : home.arpa                                               
                 Node Type . . . . . . . . . . . . : Broadcast                                               
                 IP Routing Enabled. . . . . . . . : No                                                      
                 WINS Proxy Enabled. . . . . . . . : No                                                      
                 DNS Suffix Search List. . . . . . : home.arpa                                               
                                                                                                             
              Ethernet adapter Ethernet 2:                                                                   
                                                                                                             
                 Connection-specific DNS Suffix  . :                                                         
                 Description . . . . . . . . . . . : Realtek PCIe 5GbE Family Controller                     
                 Physical Address. . . . . . . . . : 34-C8-D6-B4-01-55                                       
                 DHCP Enabled. . . . . . . . . . . : No                                                      
                 Autoconfiguration Enabled . . . . : Yes                                                     
                 IPv4 Address. . . . . . . . . . . : 192.168.10.9(Preferred)                                 
                 Subnet Mask . . . . . . . . . . . : 255.255.255.0                                           
                 Default Gateway . . . . . . . . . :                                                         
                 NetBIOS over Tcpip. . . . . . . . : Enabled                                                 
                                                                                                             
              Ethernet adapter Ethernet:                                                                     
                                                                                                             
                 Connection-specific DNS Suffix  . : home.arpa                                               
                 Description . . . . . . . . . . . : Killer E2600 Gigabit Ethernet Controller                
                 Physical Address. . . . . . . . . : B0-4F-13-0B-FD-16                                       
                 DHCP Enabled. . . . . . . . . . . : Yes                                                     
                 Autoconfiguration Enabled . . . . : Yes                                                     
                 IPv4 Address. . . . . . . . . . . : 192.168.9.100(Preferred)                                
                 Subnet Mask . . . . . . . . . . . : 255.255.255.0                                           
                 Lease Obtained. . . . . . . . . . : Saturday, November 9, 2024 12:35:04 PM                  
                 Lease Expires . . . . . . . . . . : Sunday, November 17, 2024 12:35:03 PM                   
                 Default Gateway . . . . . . . . . : 192.168.9.253                                           
                 DHCP Server . . . . . . . . . . . : 192.168.9.253                                           
                 DNS Servers . . . . . . . . . . . : 192.168.3.10                                            
                 NetBIOS over Tcpip. . . . . . . . : Enabled                                                 
                                                                                                             
              Ethernet adapter vEthernet (WSL):                                                              
                                                                                                             
                 Connection-specific DNS Suffix  . :                                                         
                 Description . . . . . . . . . . . : Hyper-V Virtual Ethernet Adapter                        
                 Physical Address. . . . . . . . . : 00-15-5D-AF-59-50                                       
                 DHCP Enabled. . . . . . . . . . . : No                                                      
                 Autoconfiguration Enabled . . . . : Yes                                                     
                 Link-local IPv6 Address . . . . . : fe80::15f4:5c26:699:97d7%27(Preferred)                  
                 IPv4 Address. . . . . . . . . . . : 172.29.64.1(Preferred)                                  
                 Subnet Mask . . . . . . . . . . . : 255.255.240.0                                           
                 Default Gateway . . . . . . . . . :                                                         
                 DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1                                      
                                                     fec0:0:0:ffff::2%1                                      
                                                     fec0:0:0:ffff::3%1                                      
                 NetBIOS over Tcpip. . . . . . . . : Enabled                                                 
              

              That 192.168.9.100 is my normal network connection, the 192.168.10.9 is a 5ge interface I have connected directly to my NAS with also a 5ge connection that I use only for transfer of files between my nas and pc. The 172.29.64.1 is interface used only for the WSL instance I run on my PC..

              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

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

                @johnpoz

                Keep in mind what L2 are those 192.168.10 showing up on - to detect if you have dhcp server you don't know about - you would need to be on that same L2 network

                What network are those .10 showing up on - your 2 your 4 or your 5?

                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

                M 1 Reply Last reply Reply Quote 0
                • M
                  Modesty @johnpoz
                  last edited by

                  Hi, thanks for answer.

                  @johnpoz said in Bizarre IP in my LAN:

                  @johnpoz

                  Keep in mind what L2 are those 192.168.10 showing up on - to detect if you have dhcp server you don't know about - you would need to be on that same L2 network

                  That is may not be possible, I dont have a .10 network, how can I log in to it?
                  I tried network VLAN_5_LEILIGHET, no ping response from 192.168.10.18 + .24

                  What network are those .10 showing up on - your 2 your 4 or your 5?

                  The .10 is only visible on unifi controller, not in DHCP leases on pfSense

                  the .10 is to a sonos device, in a apartment I rent out.
                  Can it be its ovn dhcp server?
                  Can it be some issues due to 10 days ago my dhcp was on only192.168.10.0/24

                  .2 is my lan, .4 and .5 is VLANs

                  f2727833-2958-4187-b011-366eacbbe2c6-image.png
                  b56938c8-5ce4-4580-afc5-71a0bf91d7a2-image.png

                  Everything can be rebuilt!

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

                    @Modesty said in Bizarre IP in my LAN:

                    That is may not be possible, I dont have a .10 network

                    You have a L2 they are showing up on if your seeing the traffic in pfsense.. You understand the difference between L2 and L3?

                    Where exactly are you seeing that in pfsense - the firewall, if so what interface does the firewall log the traffic on?

                    You can boot a client in the unifi controller

                    Click on the client in the unifi controller and look at the little gear icon

                    reconnect.jpg

                    Can it be some issues due to 10 days ago my dhcp was on only192.168.10.0/24

                    You mean you use to a hand out 192.168.10 addresses from pfsense dhcp? It could be the client not wanting to change its address.. Iot devices are not always that smart ;) Have seen iot devices once get an IP from dhcp never want to change it, because they never ask for dhcp again.. You have to like completely reset the device.

                    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

                    M 1 Reply Last reply Reply Quote 0
                    • M
                      Modesty @johnpoz
                      last edited by

                      Thanks @johnpoz Bizarre IP in my LAN:

                      You have a L2 they are showing up on if your seeing the traffic in pfsense.

                      As I wrote:
                      "The .10 is only visible on unifi controller, not in DHCP leases on pfSense."

                      I have done 36b34e5e-f01e-44e3-ba81-de74fb3726d1-image.png
                      Still goes back to .10, this is why I state bizarre ip in my LAN

                      I have not restarted the sonos, its in an apartment I dont have access to.

                      Everything can be rebuilt!

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

                        @Modesty said in Bizarre IP in my LAN:

                        "The .10 is only visible on unifi controller, not in DHCP leases on pfSense."

                        Did I say anything about dhcp leases?? So your not seeing any firewall traffic blocking these 192.168.10 address?

                        this is why I state bizarre ip in my LAN

                        So which one of these networks .2 .4 or .5 is your LAN in pfsense?

                        You say your only have .2 4 an 5.. Yet your pc also has a 192.168.88 address.

                        Maybe it would help if you actually draw up a picture of how you have your network setup..

                        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

                        M 1 Reply Last reply Reply Quote 0
                        • M
                          Modesty @johnpoz
                          last edited by

                          @johnpoz said in Bizarre IP in my LAN:

                          Maybe it would help if you actually draw up a picture of how you have your network setup..

                          1d156f70-b244-4e69-9ddc-02d9dd670d29-image.png

                          This is not my expertice, so sorry if I'm not 100%

                          In pfSense box I dont se .10, only on unify controller.

                          So where does .10 come from?

                          You say your only have .2 4 an 5.. Yet your pc also has a 192.168.88 address.

                          I think this is on my PC, some service, maybe NordVPN, I dont know to be honest.

                          M

                          Everything can be rebuilt!

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

                            @Modesty again to mention that these IOT devices sometimes will not give up an old IP.. You stated you use to run a 192.168.10 network.. So reset these sonos devices or log into them, put a 192.168.10 address on your device and change their IPs to what they should be for the network you have them on, your lan on 192.168.2?

                            Or just factory reset them. Or forget network, etc.

                            If you want to check if you have some rouge dhcp server, you would have to connect to whatever vlan/network these sonos are on - in your unifi controller what ssid are they connecting to, what network is that suppose to be currently?

                            edit: here I set my phone to use a IP that is not on my network.. And the unifi controller sees it.. If you had a rouge dhcp server you would think you would see more than these sonos devices on the different IP scheme.. But since its the sonos only, my guess would be at one time they had those IPs when you were running the 192.168.10 network, and they don't want to give it up - either they are set static on the device, or their iot stack is shit and they are not getting the new IP from your current dhcp server range..

                            phone.jpg

                            You will need to either login to them and fix the static, or reset them so they get a new dhcp IP.

                            I had a thermostat that was like this - pos! once it got a IP from dhcp it would never ask for dhcp again, it would just continue to use the IP it got originally.. I had to go on the thermostat and reset the whole network.. Then when I connected it got an IP on the current network, and set a reservation for it so it would never cuase a possible dupe IP issue because it wasn't renewing its lease.

                            edit2: a quick google found this about sonos

                            https://www.reddit.com/r/sonos/comments/193fmti/sonos_devices_dont_release_dhcp_assignments/

                            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

                            M 1 Reply Last reply Reply Quote 0
                            • M
                              Modesty @johnpoz
                              last edited by

                              @johnpoz
                              Thanks, I did reset them and reinstalled them , now they behave like kids ;-)

                              Everything can be rebuilt!

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

                                @Modesty said in Bizarre IP in my LAN:

                                now they behave like kids ;-)

                                hahah - not sure how to take that, you mean they are working correctly or are they still acting up - hahah ;)

                                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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