Attempting to add uplinks on a Tier-0 gateway fails with error message: "Edge Node /infra/sites/default/enforcement-points/default/edge-clusters/8a74#####-####-####-####-#####da1f/edge-nodes/0 cannot be used across different tier-0s. (Error code: 503102)"

Products

• VMware NSX

Issue/Introduction

• The following error message is seen when trying to add uplinks to the new Tier-0 GW:
  
  
  
  
• The Edge cluster added to this new Tier-0 GW is already in use by another Tier-0 GW:
  
  

Environment

VMware NSX-T
VMware NSX

Cause

Using a single Edge cluster for more than one Tier-0 GW is not supported.

Resolution

Either:

1. Create a new Edge cluster out of existing Edge VMs or newly created Edge VMs, which can then be added to the Tier-0 GW allowing for the uplinks to then be connected successfully. 
2. To conserve resources by sharing a single Tier-0 and its edge nodes, create Tier-0 VRF GW's from a parent Tier-0 GW.  This has the added benefit of allowing tenants to use overlapping IP addresses while maintaining traffic isolation.

Additional Information

For more information about the use cases for Tier-0 VRF GW's or for more understanding as to the process of deploying and configuring Tier-0 VRF GW's, please refer to the document linked below:
Tier-0 VRF Gateways