In an Edge cluster with more than two nodes, only two Edge nodes are designated as an Active/Standby pair of L2 forwarders for federated inter-site East-West communication.

Products

• VMware NSX

Issue/Introduction

In a federated NSX environment, it is worth noting that only two Edge nodes are designated with Active and Standby roles for inter-site L2 East-West forwarding, regardless of the size of the associated Edge cluster (e.g., a 4-node or 8-node cluster).

Environment

VMware NSX

Cause

Only Active/Standby Edge node placement supports L2 East/West inter-site forwarding (federated). For instance, even if there are four Edge nodes configured in Active/Active mode. However, for Tier-0 upstream North/South communication, all four Edge nodes in Active/Active mode will be utilized.

Resolution

This is expected behavior. To identify which edge nodes were selected as active/standby, following command can be used (on edge CLI):

Edge> get logical-switch <segment-UUID> l2forwarders

Logical Switch
UUID              : <>
VNI               : 66560
Global VNI        : 121081
L2Forwarder State : up
TCN notification  : active

 

This information is also available from NSX GUI for a segment: