External Connections creation fails with Error code: 640107

Products

• VMware NSX

Issue/Introduction

• Creation of External Connections fails with the following error:
  

  Error: Failed to create/update gateway Connection /infra/gateway-connections/<Tier-0>. Not allowed to enable both allow_private in Advertise Outbound Networks and enable_snat in NAT config. (Error code: 640107)

  

• Both "Provider Outbound SNAT" and "Private - Transit Gateway IP Blocks" are enabled.

Environment

NSX 9.1

Cause

Due to product limitations, only one of either "Provider Outbound SNAT" or "Private - Transit Gateway IP Blocks" can be enabled.

Resolution

Disable either "Provider Outbound SNAT" or "Private - Transit Gateway IP Blocks" and retry the creation.