Overview Of Vrrp - Dell PowerConnect B-FCXs Configuration Manual

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Overview

Overview of VRRP

VRRP is a protocol that provides redundancy to routers within a LAN. VRRP allows you to provide
alternate router paths for a host without changing the IP address or MAC address by which the host
knows its gateway. Consider the situation shown in
FIGURE 150
Switch 1 as the host default gateway out of the subnet. If this interface goes down, Host1 is cut off
from the rest of the network. Switch 1 is thus a single point of failure for Host1 access to other
networks.
If Switch 1 fails, you could configure Host1 to use Switch 2. Configuring one host with a different
default gateway might not require too much extra administration. However, consider a more
realistic network with dozens or even hundreds of hosts per subnet; reconfiguring the default
gateways for all the hosts is impractical. It is much simpler to configure a VRRP virtual router on
Switch 1 and Switch 2 to provide a redundant path for the hosts.
Figure 151
configured on Switch 1 and Switch 2.
1102
Switch 1 is Host1 default gateway but is a single point of failure
Internet
or
Enterprise Intranet
e 2/4
Switch 1
e 1/6 192.53.5.1
Default Gateway
shows the same example network shown in
Figure 150.
Internet
or
Enterprise Intranet
e 3/2
Switch 2
e 1/5
Host1
102.53.5.1
Figure 150, but with a VRRP virtual router
PowerConnect B-Series FCX Configuration Guide
53-1002266-01