Upgrading System Images
The controller is shipped with a pre-installed system image, containing the complete FortiWLC (SD) software. This image is loaded when the controller boots. As new software releases become available, you may decide to upgrade the system image.
Each release is accompanied by a Release Notes file on the documentation CD, which include procedures for upgrading different types of system configurations to the current release. Be sure to use the procedure included in the Release Notes when you choose to upgrade your system, as they provide the most up-to-date procedures.