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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.
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 configurations must be identical on both
sides of the trunk to ensure the same behavior on both sides.
Setting up VLT
The following figure shows the sample VLT topology.
Figure 128. Sample VLT Topology
In PMUX VLT, you can choose any uplink ports for configuring VLT.
NOTE: Ensure the connectivity to ToR from each Aggregator.
To enable VLT and verify the configuration, 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
2. Verify the VLT configurations.
show interface port-channel brief
EXEC mode
Dell# show interfaces port brief
Codes: L - LACP Port-channel
O - OpenFlow Controller Port-channel
LAG Mode Status Uptime Ports
127 L2 up 00:18:22 Fo 0/33 (Up)<<<<<<<<ICL LAG
812
PMUX Mode of the IO Aggregator