Alcatel-Lucent 7450 ESS Series, Configuration Manual, Page: 246 / 540

Page 246 7450 ESS OS Router Configuration Guide
VRRP Overview
The Virtual Router Redundancy Protocol (VRRP) for IPv4 is defined in the IETF RFC 3768,
Virtual Router Redundancy Protocol . VRRP describes a method of implementing a redundant IP
interface shared between two or more routers on a common LAN segment, allowing a group of
routers to function as one virtual router. When this IP interface is specified as a default gateway on
hosts directly attached to this LAN, the routers sharing the IP interface prevent a single point of
failure by limiting access to this gateway address. VRRP can be implemented on IES service
interfaces and on core network IP interfaces.
If the master virtual router fails, the backup router configured with the highest acceptable priority
becomes the master virtual router. The new master router assumes the normal packet forwarding
for the local hosts.
Figure 12 displays an example of a VRRP configuration.
Figure 12: VRRP Configuration
OSRG006
Non-Owner
ALA-3
vrld 100
Priority 150
Owner
ALA-2
vrld 100
Non-Owner
ALA-1
vrld 100
Priority 200
Internet
Backup Master Backup
Virtual
Router ID
(VRID)