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    DHCP option 43 setup for VOIP Phones

    Scheduled Pinned Locked Moved DHCP and DNS
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    • Z
      zpayne
      last edited by

      I am trying to use DHCP option 43 to set the VLAN for a VOIP Phone. I have a VLAN 10 for VOIP and VLAN 20 for DATA. I have the DATA 20 vlan untagged on the switch and the VOIP 10 vlan tagged on the switch port. I have the DHCP option 43 set on the DATA 20 vlan options as a string in HEX for the VOIP vlan tag. I am not sure what I am missing here to make this work but there is not much for information out there for this setup.

      Thanks,

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

        @zpayne

        Is the option going out in the DHCP packets? Is it the phones aren't accepting it?

        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...

        Z 1 Reply Last reply Reply Quote 0
        • Z
          zpayne @JKnott
          last edited by

          @jknott From what I am getting from a capture the option is not going out.

          1 Reply Last reply Reply Quote 0
          • M
            michmoor LAYER 8 Rebel Alliance
            last edited by

            @zpayne are you setting it in the DHCP Server settings in pfsense (assuming that’s your dhcp server)

            Firewall: NetGate,Palo Alto-VM,Juniper SRX
            Routing: Juniper, Arista, Cisco
            Switching: Juniper, Arista, Cisco
            Wireless: Unifi, Aruba IAP
            JNCIP,CCNP Enterprise

            Z 1 Reply Last reply Reply Quote 0
            • Z
              zpayne @michmoor
              last edited by

              @michmoor Yes, that is correct, I have DHCP set up on the vlan 20 and vlan 10.

              M 1 Reply Last reply Reply Quote 0
              • M
                michmoor LAYER 8 Rebel Alliance @zpayne
                last edited by

                @zpayne what VOIP phone do you have?

                Firewall: NetGate,Palo Alto-VM,Juniper SRX
                Routing: Juniper, Arista, Cisco
                Switching: Juniper, Arista, Cisco
                Wireless: Unifi, Aruba IAP
                JNCIP,CCNP Enterprise

                Z 1 Reply Last reply Reply Quote 0
                • Z
                  zpayne @michmoor
                  last edited by

                  @michmoor I am using Grandstream (GRP Series) phones connecting back to a Grandstream UCM. The are supposed to use option 43 to get the vlan ID and I have the set via hex with a string type on the option.

                  M 1 Reply Last reply Reply Quote 0
                  • M
                    michmoor LAYER 8 Rebel Alliance @zpayne
                    last edited by

                    @zpayne
                    Are you formatting it correctly in pfsense?
                    You got a screenshot?
                    https://www.grandstream.com/hubfs/Product_Documentation/DHCP_Options_Guide_Linux.pdf

                    Firewall: NetGate,Palo Alto-VM,Juniper SRX
                    Routing: Juniper, Arista, Cisco
                    Switching: Juniper, Arista, Cisco
                    Wireless: Unifi, Aruba IAP
                    JNCIP,CCNP Enterprise

                    Z 1 Reply Last reply Reply Quote 0
                    • Z
                      zpayne @michmoor
                      last edited by

                      @michmoor Here is what I have it set like on the gui

                      Boot Options.JPG

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

                        @zpayne

                        Here's some more info that might help:

                        VLAN ID Discovery over DHCP

                        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...

                        Z 1 Reply Last reply Reply Quote 0
                        • Z
                          zpayne @JKnott
                          last edited by

                          @jknott So I recieved this from the vendor, but I am still not able to get the data to go out. I have set this like recommended here.

                          https://service.snom.com/display/wiki/DHCP+options#DHCPoptions-Option43(vendor-encapsulated-options)

                          You're using DHCP option 132 and 133 using for the VLAN tags in the router,
                          although, to have this working you have to encapsulate in the DHCP 43, encapsulate the content of DHCP option 132 for the VLAN

                          So,
                          You'll need to configure the devices from Network -> Advanced Settings and set these values as follows:

                          • Enable DHCP VLAN: Enabled.
                          • Enable Manual VLAN Configuration: Disabled.
                          • Enable LLDP: Disabled.

                          Then, on a router, you will need to set the DHCP option 43 as described on the following link:
                          ** https://service.snom.com/display/wiki/DHCP+options#DHCPoptions-Option43(vendor-encapsulated-options)

                          According the link , For example,
                          for VLAN 10 should be
                          84:03:31:30:00;

                          for VLAN 20 should be
                          84:03:32:30:00;

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