Chapter 9 High Availability for FortiOS 5.0 : VRRP : Configuring VRRP
  
Configuring VRRP
To configure VRRP you must configure two or more FortiGate interfaces or routers with the same virtual router ID and IP address. Then these FortiGate units or routers can automatically join the same VRRP group. You must also assign priorities to each of the FortiGate units or routers in the VRRP group. One of the FortiGate units or routers must have the highest priority to become the master. The other FortiGate units or routers in the group are assigned lower priorities and become backup units. All of the units in the VRRP group should have different priorities. If the master unit fails, VRRP automatically fails over to the remaining unit in the group with the highest priority.
You configure VRRP from the FortiGate CLI by adding a VRRP virtual router to a FortiGate interface. You can add VRRP virtual routers to multiple FortiGate interfaces and you can add more than one virtual router to the same interface.