The first possibility entails assigning the same MAC and the same IP address to all of the routers in the VRRP group on the WAN side. The routers are then connected to a commonly used DSL line, for example by a switch. In order to avoid address conflicts, only one router may actually react to these addresses on its WAN side, which is achieved through the use of VRRP.
- Since the router closes its WAN connection when the last virtual router switches to backup mode, this condition is guaranteed to be met if only one virtual router has been defined.
- In the backup scenario, the necessary requirement is also fulfilled because the primary connection is guaranteed to have been terminated or else the backup router would not have become master.
