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    No DHCP for VLAN 5

    Scheduled Pinned Locked Moved DHCP and DNS
    53 Posts 4 Posters 8.1k Views
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    • JKnottJ
      JKnott @NasKar
      last edited by

      @NasKar

      Can you provide that as a download file. It makes it a lot easier to read in Wireshark.

      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...

      N 1 Reply Last reply Reply Quote 0
      • N
        NasKar @JKnott
        last edited by

        @JKnott
        https://www.dropbox.com/s/re22sqgcgg5tjw7/packetcapture.cap?dl=0

        Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz
        2 CPUs: 1 package(s) x 2 core(s)
        AES-NI CPU Crypto: No
        2 Gigs Ram
        SSD with ver 2.4.0
        IBM Intel Pro PCI-E Quad Port 10/100/1000 Server Adapter 39Y6138 (K210320)

        JKnottJ 1 Reply Last reply Reply Quote 0
        • JKnottJ
          JKnott @NasKar
          last edited by JKnott

          @NasKar

          You can atttach files here. You don't have to use Dropbox.

          However, here's what's in that offer:

          Frame 3: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits)
          Ethernet II, Src: Gifa_01:7b:7a (40:62:31:01:7b:7a), Dst: Apple_1e:97:af (f0:c3:71:1e:97:af)
          Internet Protocol Version 4, Src: 192.168.5.1, Dst: 192.168.5.41
          User Datagram Protocol, Src Port: 67, Dst Port: 68
          Bootstrap Protocol (Offer)
          Message type: Boot Reply (2)
          Hardware type: Ethernet (0x01)
          Hardware address length: 6
          Hops: 0
          Transaction ID: 0x037309f6
          Seconds elapsed: 0
          Bootp flags: 0x0000 (Unicast)
          Client IP address: 0.0.0.0 <---- This says the client didn't have an address previously. Typically, it would be the last used address]
          Your (client) IP address: 192.168.5.41 <---- This is what the server is offering.
          Next server IP address: 0.0.0.0
          Relay agent IP address: 0.0.0.0
          Client MAC address: Apple_1e:97:af (f0:c3:71:1e:97:af)
          Client hardware address padding: 00000000000000000000
          Server host name not given
          Boot file name not given
          Magic cookie: DHCP
          Option: (53) DHCP Message Type (Offer)
          Length: 1
          DHCP: Offer (2)
          Option: (54) DHCP Server Identifier
          Length: 4
          DHCP Server Identifier: 192.168.5.1
          Option: (51) IP Address Lease Time
          Length: 4
          IP Address Lease Time: (86400s) 1 day
          Option: (1) Subnet Mask
          Length: 4
          Subnet Mask: 255.255.255.0
          Option: (3) Router
          Option: (6) Domain Name Server
          Option: (15) Domain Name
          Option: (255) End
          Padding: 000000000000000000000000000000

          As far as I can see, this appears OK. So, the next step would be for the client to request the address, which I don't see. Does this Apple device work on other networks? Do other devices work on this VLAN?

          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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          • N
            NasKar
            last edited by

            the iPhone works on another wireless network on Vlan 40 without issue and other computers in the house can't connect to the VLAN 5 network anymore. I tried to attach the capture with the upload a file option but it kept giving an error. Any thought on were to look for the problem?

            Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz
            2 CPUs: 1 package(s) x 2 core(s)
            AES-NI CPU Crypto: No
            2 Gigs Ram
            SSD with ver 2.4.0
            IBM Intel Pro PCI-E Quad Port 10/100/1000 Server Adapter 39Y6138 (K210320)

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

              So pfsense is sending the offer.. So its not pfsense issue.. You need to look why the client is not taking it, or why its not getting 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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              • N
                NasKar
                last edited by

                Thanks that's what I need to know "it's not a pfsense issue"

                Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz
                2 CPUs: 1 package(s) x 2 core(s)
                AES-NI CPU Crypto: No
                2 Gigs Ram
                SSD with ver 2.4.0
                IBM Intel Pro PCI-E Quad Port 10/100/1000 Server Adapter 39Y6138 (K210320)

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

                  pfsense sees the discover, and sends an offer. Then another discover, so another offer, etc.. You need validate that client is actually getting it... Can you connect a laptop or something to this wifi network and sniff on it? I am not aware of sniffing on a iphone ;)

                  If there is - that could be useful!

                  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

                  N 1 Reply Last reply Reply Quote 0
                  • N
                    NasKar @johnpoz
                    last edited by

                    @johnpoz
                    I have a laptop but it can't connect to that wifi

                    Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz
                    2 CPUs: 1 package(s) x 2 core(s)
                    AES-NI CPU Crypto: No
                    2 Gigs Ram
                    SSD with ver 2.4.0
                    IBM Intel Pro PCI-E Quad Port 10/100/1000 Server Adapter 39Y6138 (K210320)

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

                      Why can you not connect 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

                      1 Reply Last reply Reply Quote 0
                      • N
                        NasKar
                        last edited by

                        I have a windows destop connected to vlan 5. Would that work? Don't know how to do sniffing. Do you have a link?

                        Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz
                        2 CPUs: 1 package(s) x 2 core(s)
                        AES-NI CPU Crypto: No
                        2 Gigs Ram
                        SSD with ver 2.4.0
                        IBM Intel Pro PCI-E Quad Port 10/100/1000 Server Adapter 39Y6138 (K210320)

                        JKnottJ 1 Reply Last reply Reply Quote 0
                        • JKnottJ
                          JKnott @NasKar
                          last edited by

                          @NasKar said in No DHCP for VLAN 5:

                          have a windows destop connected to vlan 5. Would that work? Don't know how to do sniffing. Do you have a link?

                          Yes, it should work find. It works the same way via WiFi or Ethernet. You can install Wireshark on the computer.

                          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...

                          1 Reply Last reply Reply Quote 0
                          • GrimetonG
                            Grimeton @NasKar
                            last edited by

                            @NasKar Stupid question: You have the VLAN-tags enabled/disabled correctly on the switch and on the firewall? If you don't run tcpdump with -vvv you do not see the vlan tags and you'll be chasing ghosts....

                            JKnottJ 1 Reply Last reply Reply Quote 0
                            • N
                              NasKar
                              last edited by

                              I have wireshark on the windows computer. Don't know how to use it.

                              @Grimeton said in No DHCP for VLAN 5:

                              Stupid question: You have the VLAN-tags enabled/disabled correctly on the switch and on the firewall? If you don't run tcpdump with -vvv you do not see the vlan tags and you'll be chasing ghosts....

                              Everything was working well earlier today and I can login to another wireless VLAN on the same access point so I presume it is not a problem with my switches. Is that correct?

                              Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz
                              2 CPUs: 1 package(s) x 2 core(s)
                              AES-NI CPU Crypto: No
                              2 Gigs Ram
                              SSD with ver 2.4.0
                              IBM Intel Pro PCI-E Quad Port 10/100/1000 Server Adapter 39Y6138 (K210320)

                              GrimetonG 1 Reply Last reply Reply Quote 0
                              • GrimetonG
                                Grimeton @NasKar
                                last edited by

                                @NasKar

                                #1 Rule of networking: We don't want to assume, we want to know.

                                Depending on how your switch is configured and handles tagged frames on an untagged port: delete them, forward them untouched (QinQ), remove the tag and so on, it can work and it cannot work. It's important to VERIFY the configuration along the way.

                                Cu

                                N 1 Reply Last reply Reply Quote 0
                                • N
                                  NasKar @Grimeton
                                  last edited by

                                  @Grimeton said in No DHCP for VLAN 5:

                                  Depending on how your switch is configured and handles tagged frames on an untagged port: delete them, forward them untouched (QinQ), remove the tag and so on, it can work and it cannot work. It's important to VERIFY the configuration along the way.

                                  My setup is not ideal I have 4 netgear switches between the pfsense and the AP. Would have been best to have one switch with all the cables going directly to it. I can try to move the AP temporarily to the switch connected to the pfsense

                                  Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz
                                  2 CPUs: 1 package(s) x 2 core(s)
                                  AES-NI CPU Crypto: No
                                  2 Gigs Ram
                                  SSD with ver 2.4.0
                                  IBM Intel Pro PCI-E Quad Port 10/100/1000 Server Adapter 39Y6138 (K210320)

                                  GrimetonG JKnottJ 2 Replies Last reply Reply Quote 0
                                  • GrimetonG
                                    Grimeton @NasKar
                                    last edited by

                                    @NasKar
                                    If the interface on the pfSense is tagged and the interface on the switch is NOT tagged this can lead to all kind of confusions. Same happens when vice versa.

                                    So it's important to know that your VLAN-configuration on pfSense and on the switch is fine.

                                    As DHCP is a system that uses broadcast and relies more on L2 than on L3, having a valid and working VLAN-config is important.

                                    1 Reply Last reply Reply Quote 0
                                    • JKnottJ
                                      JKnott @Grimeton
                                      last edited by

                                      @Grimeton

                                      Given the phone is sending out discovers and receiving offers, that's not an issue. Also, you'd not see VLAN tags on a switch port that's already been assigned to a VLAN.

                                      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...

                                      GrimetonG 1 Reply Last reply Reply Quote 0
                                      • GrimetonG
                                        Grimeton @JKnott
                                        last edited by

                                        @JKnott I can tell you from experience that all you've just written is false.

                                        JKnottJ 1 Reply Last reply Reply Quote 0
                                        • JKnottJ
                                          JKnott @NasKar
                                          last edited by

                                          @NasKar

                                          Four switches is not a problem if they're configured properly. You have a VLAN. I assume you have the VLAN configured on pfSense and any switch that has to pass VLAN frames configured appropriately. At some point, either a switch or in the AP, the VLAN frames are converted to native frames, by removing the VLAN tags. However, given that you're getting an offer after a discover, there is communication between the iPhone and DHCP server, so I doubt VLAN tags are the problem.

                                          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...

                                          GrimetonG 1 Reply Last reply Reply Quote 0
                                          • JKnottJ
                                            JKnott @Grimeton
                                            last edited by

                                            @Grimeton

                                            False in what way? I have viewed the captured traffic in Wireshark and I can see the discover, coming from the iPhone, followed immediately by the offer, coming from the DHCP server. That tells me the phone and server are communicating up to that point. The next step is for the phone to request the offered address, but that's not happening. The question is why. If it was a VLAN issue, we'd see the discover, but not the offer.

                                            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...

                                            1 Reply Last reply Reply Quote 0
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