20 VRRP CONFIGURATION GUIDE
Single VRRP Group
Configuration
Virtual Router Redundancy Protocol (VRRP) is an error-tolerant protocol defined in
RFC 2338. In LANs with multicast or broadcast capabilities (such as Ethernet),
VRRP can avoid single point failure through establishing backup links without
modifying the configuration of dynamic routing protocols and router discovery
protocols.
You can add two or more switches into a single VRRP group, which can provide
two or more reliable links to the outside networks, therefore avoiding
communication interruption resulting from single- or multi- point failure.
Network Diagram Figure49 Network diagram for VRRP
Networking and
Configuration
Requirements
Host A accesses Host B on the Internet, with the VRRP group consisting of Switch
A and Switch B as its default gateway.
VRRP group settings:
■VRRP group number: 1
■Virtual router IP address of the VRRP group: 202.38.160.111.
■Switch A acts as the master.
■Switch B acts as the backup, and works in the preemptive mode.
LSW A
Host A
Internet
Host B
LSW B
Vlan-int3
10.100.10.2/24
Virtual IP address
202.38.160.111/24
Vlan-int2
202.38.160.1/24
Vlan-int2
202.38.160.2/24
202.38.160.3/24
10.2.3.1/24