Switching Cisco Aironet AP between Autonomous Mode and Lightweight Mode

To use Wireless LAN Controllers manage older Cisco Aironet AP, such as Air-AP1231, you will need to convert it to lightweight mode. Occasionally, you will need to convert it back to autonomous mode and then reconvert it to lightweight mode if the AP constantly reboots itself and following message shows up in the console session:

*Mar  1 00:00:27.657: %LWAPP-3-CLIENTERRORLOG: LWAPP Crypto Init: could not start PKI session

*Mar  1 00:00:27.658: %LWAPP-3-CLIENTERRORLOG: Failed to initialize Crypto. Rebooting

*Mar  1 00:00:27.823: %SYS-5-RELOAD: Reload requested by CAPWAP CLIENT. Reload Reason: FAILED CRYPTO INIT.

*Mar  1 00:00:27.828: %LWAPP-5-CHANGED: CAPWAP changed state to DOWNXmodem file system is available.

Here is a list of software you will need to perform the tasks:

·         CiscoAironet-AP-to-LWAPP-Upgrade-Tool-v34.exe

·         TFTP server

·         LWAPP Recovery Image: c1200-rcvk9w8-tar.124-21a.JA2.tar

·         Supported IOS Image: c1200-k9w7-tar.123-7.JA1.tar

Here is the step to covert the AP to Lightweight mode:

1.       Install the Upgrade tool

2.       Connect the autonomous AP to network and get its IP. Make sure the AP is running the IOS image mentioned above.

3.       Create a text file with following content: “10.90.1.104,Cisco,Cisco,Cisco” without the quotation mark. Replace the IP address here with the AP’s IP. The sample file I used here is called “ap-file.txt”

4.       Launch the upgrading tool and fill in required field, where IP File is the text file contains AP’s IP; Select “Use Upgrade Tool TFTP Server” and points to the LWAPP image; The System IP Addr is your local machine’s IP address; Enter WLC’s IP, and credential that can add AP to controller; Select “Use Controller Time”; Click Start. The conversion process could take a few minutes. Click on Detailed Log for progress.

5.       Make sure your security policy on WLC allows the AP to join. Once it is done, you should be able to find the AP on your controller.

To convert the AP back to autonomous mode:

1.       Assign your machine with a static IP: 10.0.0.2/8, and connect it to a spare switch.

2.       Rename the IOS image to c1200-k9w7-tar.default , save it to the TFTP program’s root folder, and launch the TFTP program. Make sure “default” is the image extension – check your Folder Display Option.

3.       Plug the AP into the same VLAN port as your machine, hold the Mode button, and power on the AP.

4.       Wait the status LED turn to RED, not amber, and release the mode button. The AP will assign 10.0.0.1 to itself and download the IOS image.

Here is a reference doc from Cisco: 

http://www.cisco.com/en/US/docs/wireless/access_point/conversion/lwapp/upgrade/guide/lwapnote.html#wp160918