Deployment Guide

• Provides fast convergence if either the link or a device fails.
• Optimized forwarding with virtual router redundancy protocol (VRRP).
• Provides link-level resiliency.
• Assures high availability.
CAUTION: Dell Networking does not recommend enabling Stacking and VLT simultaneously. If you enable both features at the
same time, unexpected behavior occurs.
As shown in the following example, VLT presents a single logical Layer 2 domain from the perspective of attached devices that have a
virtual link trunk terminating on separate chassis in the VLT domain. However, the two VLT chassis are independent Layer2/Layer3 (L2/L3)
switches for devices in the upstream network. L2/L3 control plane protocols and system management features function normally in VLT
mode. Features such as VRRP and internet group management protocol (IGMP) snooping require state information coordinating between
the two VLT chassis. IGMP and VLT congurations must be identical on both sides of the trunk to ensure the same behavior on both sides.
Setting up VLT
The following gure shows the sample VLT topology.
Figure 35. Sample VLT Topology
Ports 33 and 37 are used as ICL links and these two 40G ports are connected back to back between the two Aggregators.
In PMUX VLT, you can choose any uplink ports for conguring VLT.
NOTE
: Ensure the connectivity to ToR from each Aggregator.
To enable VLT and verify the conguration, follow these steps.
1 Enable VLT in node 1 and 2.
stack-unit unit iom-mode vlt
CONFIGURATION mode
Dell(conf)#stack-unit 0 iom-mode vlt
PMUX Mode of the IO Aggregator
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