Interconnecting three sites with MCLAG

This cookbook article describes how to add a third site that interconnects a third MCLAG peer group with the existing redundancy between two sites. The links between sites 1 and 3 and sites 2 and 3 are independent; therefore, loops are avoided by using the Spanning Tree Protocol (STP).

The following tasks are covered:

1. Adding the third site
2. Checking the topology
3. Relevant configuration

This cookbook article assumes that sites 1 and 2 are already deployed. See the “HA-mode FortiGate units in remote sites” section in the FortiSwitch Managed by FortiOS 6.4 guide.

You can refer to the following topics for more information:

• HA-mode FortiGate units in remote sites
• FortiSwitch Managed by FortiOS 6.4
• MCLAG topologies