Technical Note: Two VLANs on a single port in a managed FortiSwitch
Description
Solution
Once the FortiSwitch is managed by the FortiGate go to

Choose the native VLAN and assign two or more VLANs to a switch port.

VLAN assignment may also be done in CLI:
In FortiOS version 5.2 there is no option to configure two VLANs on a single port in a managed FortiSwitch.
In FortiOS version 5.4 the possibility to assign two VLANs to a single port has been enabled.
In FortiOS version 5.4 the possibility to assign two VLANs to a single port has been enabled.
Solution
- Enable Switch Controller on the FortiGate.
- Connect the FortiSwitch to the FortiGate on the designated ports.
- Configure the FortiLink port.
- Authorize the FortiSwitch.
Once the FortiSwitch is managed by the FortiGate go to
- WiFi & Switch Controller > FortiSwitch VLANs
- Select Create New
- Input Interface Name, VLAN ID, Color, and IP/Network Mask

Choose the native VLAN and assign two or more VLANs to a switch port.
- Go to WiFi & Switch Controller > FortiSwitchPorts
- Click a row to select a port
- Right-click and select Assign VLANs > Native VLAN and select a VLAN from the list
- Right-click and select Assign VLANs > Allowed VLANs
- In the dialog box, select an allowed VLAN
- Click the + icon to add another allowed VLAN

VLAN assignment may also be done in CLI:
config switch-controller managed-switch
edit <Switch ID>
config ports
edit <port name>
set vlan <VLAN name>
set allowed-vlans <VLAN name>
next
end
end
