Preparing for the Upgrade
You must complete these tasks before beginning the upgrade from autonomous to lightweight mode:
- Prepare the infrastructure so that the upgraded lightweight access point discovers a controller.
- The autonomous access points must be running Cisco IOS Release 12.3(7)JA or later to perform the lightweight mode conversion. If necessary, upgrade the access point to Cisco IOS Release 12.3(7)JA or later. For C3201WMIC, upgrade to 12.3(8)JK or later.
- Prepare the controller for the upgrade process.
- Download the Autonomous to Lightweight Mode Upgrade Tool and the upgrade image file from Cisco.com
Preparing the Infrastructure
No lightweight access point can operate independently from a WLC. Each lightweight access point must discover a WLC, issue an LWAPP join request, and if successful, receive a join response to become joined to a controller.
The LWAPP discovery algorithm follows these steps:
- Initiates an IP subnet broadcast of an LWAPP controller discovery message. If the controller management interface is on the same IP subnet as the lightweight access point, this discovery mechanism is successful.
- Lists the previously joined controllers. This discovery mechanism requires prior success joining an access point and controller.
- Establishes over-the-air provisioning (OTAP). If OTAP is turned on, access points advertise their controller(s) over the air. New access points discover the controller based on the OTAP messages. OTAP is turned off by default on the controllers. OTAP is not supported for controller discovery during the upgrade process from autonomous to lightweight access point. After an access point is fully migrated to the lightweight mode, OTAP is used to discover controllers.
- Uses DHCP option 43. This vendor-specific option can return one or more controller IP addresses to an access point in the DHCP offer message. The access point sends an LWAPP join message to the controller.
- Establishes DNS resolution of CISCO-LWAPP-CONTROLLER.localdomain. If the access point can resolve the name, it issues an LWAPP join message to the resolved IP address.
- Reboots and repeats starting with Step 1
Upgrading the 1252 AP to Lightweight Mode
The Cisco Utility version 3.2 does not support the conversion of 1140 and 1250 series autonomous access points to lightweight mode. To convert these autonomous access points to lightweight mode, telnet to the access point and issue the following command to upgrade the IOS:
archive download-sw /overwrite /reload tftp://location/image-name
- Remote AP doesn’t register to the Controller. Telnet to the AP and enter the command lwapp ap controller ip address a.b.c.d