3com 8807 User Guide

C

HAPTER

 53: VRRP C

ONFIGURATION

Figure 157   Network diagram for virtual router

This virtual router has its own IP address: 10.100.10.1 (which can be the interface 
address of a switch within the virtual router). The switches within the virtual router 
have their own IP addresses (such as 10.100.10.2 for the Master switch and 
10.100.10.3 for the Backup switch). The host on the LAN only knows the IP 
address of this virtual router 10.100.10.1 (usually called as virtual IP address of 
virtual router), but not the specific IP addresses 10.100.10.2 of the Master switch 
and 10.100.10.3 of the Backup switch. They configure their own default routes as 
the IP address of this virtual router: 10.100.10.1. Therefore, hosts within the 
network will communicate with the external network through this virtual router. If 
a Master switch in the virtual group breaks down, another Backup switch will 
function as the new Master switch to continue serving the host with routing to 
avoid interrupting the communication between the host and the external 
networks.

The following sections describe the VRRP configuration tasks:

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Ethernet

Master

Host 1

Host 2

Host 3

10.100.10.7

10.100.10.8

10.100.10.9

Virtual IP address10.100.10.1

Network

Backup

Virtual IP address10.100.10.1

Actual IP address10.100.10.2

Actual IP address10.100.10.3