Limitation of NSX-T edge multi vtep scenario

Products

• VMware NSX

Issue/Introduction

In Edge Multi vtep scenario, disconnecting one vNIC on the Edge causes all traffic to drop

Environment

VMware NSX-T Data Center

VMware NSX-T Data Center 3.x

VMware NSX 4.x

Cause

In Edge multiTEP configuration, when a VNIC of the Edge VM is disconnected, in the current implementation, the failed TEP IP and MAC are moved to another vNIC. If the host switch is not configured in promiscuous mode or with MAC learning, the traffic is blackholed.

Resolution

This is a product limitation

Workaround:

• Enable promiscuous and Forged Transmits mode to accept.
  • Login to vcenter server 
  • Go to Menu > Networking > Distributed Switch > Portgroup 
  • Right click on port group Edit setting
  • Click Security > Promiscuous mode Accept > Forged transmits Accept.