NSX Edge Nodes become Active/Active in an Active/Standby configuration "Split Brain"

Products

• VMware NSX

Issue/Introduction

• Edge Nodes are configured in an Active/Standby configuration.
• Edge Node loses communication with NSX Managers and other Edge Nodes. 
• Both Active and Standby Edges become Active/Active.

Environment

VMware NSX

Cause

In a situation where one edge loses communication to the other edge node and NSX Managers, the standby edge detects the Active edge has become unreachable and is in effect down. The Standby edge will transition to an Active state as is expected with High Availability (HA). When NSX Edge nodes are in an Active/Active state and configured for Active/Standby, it is known as Split Brain and can result in network disruption.

Resolution

This is a condition that may occur in a VMware NSX environment.

Restore connectivity to the affected Edge node so BFD communication is restored. If required, power down the standby edge node until it is feasible to restore the underlying network connectivity.