NSX Edge Tunnels down in a collapsed cluster

Products

• VMware NSX

Issue/Introduction

• In NSX-T datacenter and NSX. The edge nodes are deployed to a vCenter in a collapsed cluster (NSX edge deployed to a host that is prepared for NSX).
• The edge nodes have two networks that are connected to PortGroups in a VDS that are used for NSX overlay instead of a NVDS.
• Host transport nodes and Edge nodes are using two different TEP IP Pool, however, the backing VLAN for host TEP and edge TEP are the same. 
• While in a greenfield deployment (without any running VMs on the host that uses overlay network), not all edge TEP tunnels are up. 
• While in a brownfield deployment, the host TEPs to Edge TEPs are down.
• The down TEPs have connectivity to each other within NSX edge node VRF 0 (Tunnel). 
  
  
  
  

Environment

• VMware NSX-T datacenter
• VMware NSX 

Cause

This is caused by edge TEP and host TEP in the same VLAN. 

Resolution

To resolve this issue: 

Have two separated VLANs for NSX edge TEP and Host Transport Node TEP. 

-or-

Create an NSX managed VLAN segment and attach the edge nodes to the portgroup

 

If you are unable to apply this workaround or it does not work for you, please open a support request with Broadcom support and reference this KB.