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Figure 134. Basic VRRP Configuration
VRRP Benefits
With VRRP configured on a network, end-station connectivity to the network is not subject to a single point-of-failure.
End-station connections to the network are redundant and are not dependent on internal gateway protocol (IGP) protocols to
converge or update routing tables.
VRRP Implementation
Dell Networking OS supports a total of 2000 VRRP groups on a switch and 255 VRRP groups per interface
Within a single VRRP group, up to 12 virtual IP addresses are supported. Virtual IP addresses can belong to the primary or
secondary IP address’ subnet configured on the interface. You can ping all the virtual IP addresses configured on the Master
VRRP router from anywhere in the local subnet.
Default VRRP settings may affect the maximum number of groups that you can configure and work efficiently, as a result
of hardware throttling VRRP advertisement packets reaching the CP on the switch. To avoid throttling VRRP advertisement
packets, Dell Networking recommends increasing the VRRP advertisement interval to a value higher than the default value of 1
second.
CAUTION:
Increasing the advertisement interval increases the VRRP Master dead interval, resulting in an
increased failover time for Master/Backup election. Take caution when increasing the advertisement interval, as
the increased dead interval may cause packets to be dropped during that switch-over time.
The recommendations in the following table vary, depending on several factors; for example, address resolution protocol (ARP)
broadcasts, IP broadcasts, or spanning tree protocol (STP) before changing the advertisement interval. When the number of
packets processed by the CP processor increases or decreases based on the dynamics of the network, the advertisement
intervals in may increase or decrease accordingly.
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Virtual Router Redundancy Protocol (VRRP)