Fortigategate 600c as gateway

[mabdelwahed]

Hello, 

In my firm we have the following topology Core Switch -->Fortigate 600C--> Cisco 3845 Router (to the Internet), all my interface VLANS are created on the Core Switch and the Router is connected to EFMs for internet access and HWIC (ADSL) , i have to modify this topology to make the interface VLANs on the fortigate and from the fortigate route them to the internet through the router , how it can be done ?

[ashukla_FTNT]

Fortigate should do all the inter-vlan routing. The core switch should have only vlan configuation but it should not be doing any L3 function (inter vlan routing).

Create vlan interaces on fortigate (the ip address of these vlan interfaces should be the gateways on lan pcs).

Make sure the port from core-switch to fortigate is in trunk mode.