3com S7906E 설치 설명서

 

1-8 

Figure 1-6 VRRP in load sharing mode 

Host A

Host B

Host C

Router A

Router B

Router C

VRRP group 2

VRRP group 3

VRRP group 1 

Network

 

 

A router can be in multiple VRRP groups and hold a different priority in different group. 

In 

, three VRRP groups are present: 

z 

VRRP group 1: Router A is the master; Router B and Router C are the backups. 

z 

VRRP group 2: Router B is the master; Router A and Router C are the backups. 

z 

VRRP group 3: Router C is the master; Router A and Router B are the backups. 

For load sharing among Router A, Router B, and Router C, hosts on the LAN need to be configured to 

use VRRP group 1, 2, and 3 as the default gateways respectively. When configuring VRRP priorities, 

make sure that each router holds such a priority in each VRRP group that it will take the expected role in 

the group. 

When VRRP works in the standard protocol mode, only the master can forward packets and the 

backups are in the state of listening. Although you can create multiple VRRP groups to implement load 

sharing among multiple routers, hosts on the LAN need to be configured with different gateways, thus 

making the configuration complicated. 

When VRRP works in the load balancing mode, namely, besides virtual gateway redundancy, VRRP 

realizes load balancing. The working principle is as follows: associate a virtual IP address with multiple 

virtual MAC addresses to make each router in a VRRP group correspond to a virtual MAC address. In 

this way, each router in this VRRP group can forward packets. In the load balancing mode, you need to 

create only one VRRP group to realize load balancing among multiple routers, thus avoiding that the 

backups are always in the idle state and the network resources are not fully utilized.