Avaya P460 Manuel D’Utilisation

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Chapter 5
Avaya P460 Layer 3 Features
Avaya P460 Configuration Guide
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VRRP (Virtual Router Redundancy Protocol) Configuration
VRRP Overview
VRRP is an IETF protocol designed to support redundancy of routers on the LAN, 
and load balancing of traffic. VRRP is transparent to host stations, making it an ideal 
option when redundancy, load balancing and ease of configuration are all required.
The concept underlying VRRP is that a router can backup other routers, in addition 
to performing its primary routing functions. This redundancy is achieved by 
introducing the concept of a virtual router. A virtual router is a routing entity 
associated with multiple physical routers. One of the physical routers with which 
virtual router is associated perfoems the routing functions. This router is known as 
the master router. For each virtual router, VRRP selects a master router. If the 
selected master router fails, another router is selected as master router.
In VRRP, two or more physical routers can be associated with a virtual router, thus 
achieving extreme reliability. In a VRRP environment, host stations interact with the 
virtual router. The stations are not aware that this router is a virtual router, and are 
not affected when a new router takes over the role of master router. Thus VRRP 
fully interoperable with any host station.
You can activate VRRP on an interface using a single command while allowing for 
the necessary fine-tuning of the many VRRP parameters. For a detailed description 
of VRRP, see VRRP standards and published literature.