According to theFortiOS 7.6 Study Guideand theFortiSwitch 7.6 FortiLink Guide, several prerequisite steps and compatibility checks must be performed before a FortiGate can successfully discover, authorize, and manage a FortiSwitch or a stack of switches.
First, theSwitch Controller feature must be enabled (Option B)on the FortiGate.2By default, on many FortiGate models, the " Switch Controller " menu is hidden in the GUI to simplify the interface. Administrators must navigate toSystem > Feature Visibilityand toggle theSwitch Controllerswitch to " on " to expose the management menus required to configure FortiLink interfaces and manage FortiSwitch units.3Without this feature enabled, the FortiGate cannot act as a centralized management entity for the switch fabric.
Second, theFortiSwitchOS version must be compatible with FortiOS (Option D). While it is not strictly required to be on the " latest " version (Option A), the firmware on both devices must fall within the supported compatibility matrix provided by Fortinet. If the versions are incompatible, the FortiLink tunnel (CAPWAP) may fail to establish, or certain management features may be unavailable in the FortiOS GUI.
Regarding the incorrect options:Option Ais not a requirement because older, compatible versions are often used in stable environments.Option Cis incorrect because FortiLink interfaces are the very mechanism used for management; they must be correctly configured and enabled, not disabled, for management to function. Therefore, ensuring feature visibility and verifying the compatibility matrix are the two essential administrative requirements for establishing a managed switch stack.