Vrrp Overview - 3Com 7757 Configuration Manual

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VRRP Overview

VRRP C
ONFIGURATION
Virtual router redundancy protocol (VRRP) is a fault-tolerant protocol.
As shown in Figure 141, in general,
A default route (for example, the next hop address of the default route is
■
10.100.10.1, as shown in the following figure) is configured for every host on a
network.
The packets destined to the external network segments and sourced from
■
these hosts go through the default routes to the Layer 3 Switch, implementing
communication between these hosts and the external network.
If Switch fails, all the hosts on this segment taking Switch as the next-hop
■
through the default routes are cut off from the external network.
Figure 141 LAN Networking
Network
Switch
10.100 .10.1
10.100.10.7
Host 1
Host 2
VRRP, designed for LANs with multicast and broadcast capabilities (such as
Ethernet), settles the problem caused by switch failures.
VRRP combines a group of LAN switches, including a master switch and several
backup switches, into a virtual router, or a backup group.
Ethernet
10.100 .10 .8 10.100.10.9
Host 3