Configuring a replication from on-premises to cloud synchronization is stuck at 0% inside VMware Cloud Director Availability

Products

• VMware Cloud Director

Issue/Introduction

After configuring a new setup for VMware Cloud Director Availability(VCDA), the initial synchronization does not complete and is stuck for 0% always.

Environment

VMware Cloud Director Availability 4.7.3.1

Cause

The issue occurs because of a missing firewall rule or missing configuring ports from ESXi to VCDA On-premise site.

Resolution

To workaround the issue please open the port 44046/TCP from ESXi hosts to VMware Cloud Director Availability On-Premises Appliance.
For a better understanding about network requirements for VCDA please go through the VCDA architecture document: Deployment requirements for the On-Premises to Cloud Director Replication Appliance. 
For a better understanding about VCDA ports and protocols please go through the document: VMware Ports and Protocols