Configuring DHCP Option 82 For Wired Captive Portal Clients

DHCP Option 82 is supported for wired guest clients traffic from cnPilot 3.9-r3 image

Insert DHCP Option 82 with circuit ID and remote ID is available under

  1. WALN profile configuration
  2. L3 VLAN interface configuration and
  3. At Device level

The order of configuration priority is (which configuration takes precedence when same configuration is done at multiple places)

  1. Device level
  2. WLAN profile level
  3. L3 interface level  

Feature description:

Device level: When configured at device level along with VLAN ID / IDs, Option 82 is inserted for all the DHCP client packets leaving from the configured VALN interfaces. The DHCP option 82 configured at WLAN profiles / L3 interfaces will be ignored.

This configuration is recommended when it desired to insert option 82 both for

  • Guest access enabled wired traffic
  • Guest and without guest access enabled wireless DHCP client traffic

The configuration location information:

In Access Point: Configure - Services - Network - DHCP Option 82

In cnMaestro: Not avaible on cloud version 1.6.3-r17 and will be addedd soon.  The work around until it is availble from regular UI is make use of device-override option 

WLAN profile level: When DHCP option 82 is configured at WLAN profile, option 82 is inserted for all the DHCP client packets coming from the wireless clients.  The DHCP option 82 configured at L3 interface will be ignored.

This configuration is recommended when it is desired to insert option 82 only for DHCP client traffic coming from wireless interface. The WLAN profile can be guest access or without guest access enabled one

Note: To send DHCP Option 82 configured at WLAN profile level, WLAN VLAN shall not be part of device level DHCP Option 82 configurations  

The configuration location information: Both in AP and cnMaestro under WLAN profile 

L3 interface level: When DHCP option 82 is configured at L3 interface level, device inserts option 82 in DHCP client relayed packet

This configuration is recommended when it is desired to insert option 82 in DHCP client relayed traffic

The configuration location information: Both in AP and cnMaestro under Network - VLAN  

Note: To send DHCP Option 82 configured at L3 interface level,  WLAN profile and Device level Option 82 shall not include the VLAN ID

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