3Com Switch 8800 Advanced Software V5 Configuration Guide

Configuring VRRP for IPv4 767
In load balancing mode, multiple routers provide services at the same time. This
mode requires two or more standby groups, each of which includes a master and
one or more backups. The masters of the standby groups can be assumed by
different routers, as shown in
Figure 234.
Figure 234 VRRP in load balancing mode
A router can be in multiple standby groups and hold a different priority in different
group.
In Figure 234, three standby groups are present:
■ Standby group 1: Router A is the master; Router B and Router C are the
backups.
■ Standby group 2: Router B is the master; Router A and Router C are the
backups.
■ Standby group 3: Router C is the master; Router A and Router B are the
backups.
For load balancing among Router A, Router B, and Router C, hosts on the LAN
need to be configured to use standby group 1, 2, and 3 as the default gateways
respectively. When configuring VRRP priorities, ensure that each router holds such
a priority in each standby group that it will take the expected role in the group.
Configuring VRRP for
IPv4
Complete these tasks to configure VRRP for IPv4:
Host A
Host B
Host C
Router A
Backup
Router B
Backup
Router C
Master
Virtual router 2
Virtual router 3Virtual router 1
Master
Backup
Backup Backup
Master
Backup
Network
Task Remarks
“Enabling Users to Ping Virtual IP Addresses of Standby Groups” on
page 768
Optional
“Configuring the Association Between MAC Address and Virtual IP
Address” on page 768
Optional