Firmware upgrade in Cisco Aironet series
Retrieve new firmware
Please download new version of firmware from Cisco's support page.
The firmware should be uploaded online such as HTTP server or TFTP server. The firmware can be upgraded by the following command.
# archive download-sw /overwrite http://192.0.2.1/c1XXX-xxxx.tar
Note that the option /overwrite denotes current firmware would be overwritten by new firmware, i.e., current (old) firmware would be deleted. This option can be omitted but access points sometimes have small storage, so this option is required when storage shortage occurs. You can also use TFTP by replacing http to tftp. The IP address 192.0.2.1 is just an example, so please replace it to your server's IP address. Moreover, please replace the filename c1XXX-xxxx.tar to the path where you put new firmware.
Apply the upgrade
After the upgrade, you should reboot the access point by reload command.