Chapter 9 High Availability for FortiOS 5.0 : Full mesh HA : Example: full mesh HA configuration : Full mesh switch configuration
  
Full mesh switch configuration
The following redundant switch configuration is required:
• Two redundant switches (Sw3 and Sw4) connected to the internal network. Establish an interswitch-link (ISL) between them.
• Two redundant switches (Sw1 and Sw2) connected to the Internet. Establish an interswitch-link (ISL) between them.