Chapter 11 IPsec VPN for FortiOS 5.0 : Redundant VPN configurations
  
Redundant VPN configurations
This section discusses the options for supporting redundant and partially redundant IPsec VPNs, using route-based approaches.
The following topics are included in this section:
Configuration overview
General configuration steps
Configure the VPN peers - route-based VPN
Redundant route-based VPN configuration example
Partially-redundant route-based VPN example
Creating a backup IPsec interface