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30 Using MLAG in Dell Networking N-Series Switches | version 1.5
7 MLAG and VRRP Example
The following example scenario combines two-tier MLAG and Virtual Router Redundancy Protocol (VRRP).
Two N4032 and two N2048 switches in an MLAG configuration provide robust and high-capacity, Layer-2
transport to an access layer, N1532 switch. The N4032 switches acting aggregation/core layer provide
gateway redundancy using VRRP on MLAG interfaces.
With VRRP configured, the two switches share a common virtual IP, which is used as the gateway address
for clients on the network. One of the switches fills the role of the gateway for that address as long as it is
available. That switch is said to be the active router. If the active router becomes unavailable, the VRRP
backup peer takes over. In this way, a gateway can fail and no clients know anything happened. The backup
switch fills the gateway role seamlessly. The scenario depicted in Figure 19 combines MLAG and VRRP.
The following sections provide instructions for only MLAG domains 55 and 56 with MLAG 13. Domain 57 and
MLAG 14 would use similar commands for VLAN 20.
Note: In Figure 19, an N4032 switch splits the Layer-2 network from the Layer-3 network. MLAG does not
currently support Layer-3 VLAN termination. Recovery from a Layer-3 link failure requires a dedicated link
between MLAG peer switches to perform layer-3 routing. For more information please refer to the N-series user
guide on support.dell.com