Technical Tip: Share the same subnet/VLAN between FortiSwitch, FortiGate interface and Wireless SSID

[sachitdas_FTNT]

Description	This article describes configuration steps to share the same subnet between the FortiSwitch port, FortiGate port, and Wireless SSID
Scope	FortiGate, Managed FortiSwitch version 7.x and above.
Solution	Requirement: The client connecting to the FortiSwitch port, FortiGate port, and wireless SSID should get an IP address from the same subnet. Refer to the below example/configuration: Step 1: Configure a VLAN on FortiSwitch (Wifi & switch controller -> FortiSwitch Vlans), do not give any IP address. The interface is showing as port4 because it is the FortiLink interface (dedicated to FortiSwitch). Give a VLAN ID, for example: 100. Do not map the VLAN to any FortiSwitch port before step 2. Make sure there are no references for the VLAN.   Step 2: Configure a Software Switch Interface on FortiGate (Network -> Interfaces -> Create new interface -> Select interface type as software switch -> Map the FortiSwitch vlan100 and FortiGate physical port as interface members). Configure the software switch with IP, DHCP, and other details as required. Step 3: Now map the vlan100 to the FortiSwitch ports: Step 4: Connect a client to FortiSwitch port1 and another one to FortiGate port2 and both clients will get the IP address from vlan100. Similarly for the Wi-Fi SSID, configure the SSID in tunnel mode, make sure the SSID has no references, and then map the SSID as a member of the software switch interface.