3com 5500-SI Manual De Usuario
12
VRRP C
ONFIGURATION
VRRP Overview
Virtual router redundancy protocol (VRRP) is a fault-tolerant protocol.
As shown in Figure 37, in general,
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A default route (for example, the next hop address of the default route is
10.100.10.1, as shown in Figure 37) is configured for every host on a network.
10.100.10.1, as shown in Figure 37) is configured for every host on a network.
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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.
hosts go through the default routes to the Layer 3 Switch, implementing
communication between these hosts and the external network.
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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.
the default routes are cut off from the external network.
Figure 37 LAN Networking
VRRP, which is designed for LANs with multicast and broadcast capabilities (such as
Ethernet) settles the problem caused by switch failures.
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.
backup switches, into a virtual router, or a backup group.
Ethernet
Switch
Host 1
Host 2
Host 3
10.100.10.7
10.100.10.8
10.100.10.9
10.100.10.1
Network