Merge Provider VDC Wizard Doesn't List Certain Provider VDCs in VMware Cloud Director

Products

• VMware Cloud Director

Issue/Introduction

• When attempting to merge two Provider Virtual Data Centers (PVDCs) in VMware Cloud Director, one of the PVDCs does not appear in the merge wizard, even though both are associated with the same NSX-T Manager. This prevents the merge from proceeding through the UI.
• This article outlines the root cause of the issue and provides guidance on how to verify the underlying configuration, including steps to check relevant mappings in the VCD database to assist with resolution.

Environment

VMware Cloud Director 10.x

Cause

This issue arises because, despite sharing the same NSX-T Manager, the two PVDCs are backed by different Network Pools. VMware Cloud Director's design requires that both participating PVDCs utilize the same Network Pool (or no NSX) for a merge operation to be permitted. 

Resolution

To resolve the issue, you need to ensure both PVDCs are backed by the same Network Pool.

1. Verify Network Pool Mappings in the Cloud Director Database for both the Provider VDCs:
   • Login to VCD database from primary cell: db
     
     
2. Execute the following query to identify the Network Pool IDs (fo_id) for your PVDCs:
   • SELECT prov_vdc_id, fo_id FROM prov_vdc_logical_resource WHERE prov_vdc_id IN ( SELECT id FROM prov_vdc WHERE name = '<name of source Provider VDC>' ) AND lr_type = 'NETWORK_POOL' UNION ALL SELECT prov_vdc_id, fo_id FROM prov_vdc_logical_resource WHERE prov_vdc_id IN ( SELECT id FROM prov_vdc WHERE name = '<name of destination Provider VDC>' ) AND lr_type = 'NETWORK_POOL';
 
3. Compare the fo_id (Network Pool ID) values for both the PVDCs. If they are different, it confirms the reason why certain PVDCs are not listed during the merge operation.

Note: Merging two Provider VDCs is only supported when both are backed by the same NSX-T Manager and the same Network Pool, or when NSX-T is not used at all. For detailed requirements, refer to the official VMware documentation on prerequisites for merging PVDCs with NSX-T 

Workaround:

Option1:

1. Manually migrate workloads from one PVDC cluster to the other as needed.

Option2:

1. Delete and recreate the PVDCs using the same, shared Network Pool.

2. Once both PVDCs are aligned with the same Network Pool, retry the merge operation using the UI wizard.

Additional Information

Limitation: The VCD UI does not explicitly display the Network Pool associations for a PVDC, which can cause confusion—especially when both PVDCs are sharing the same NSX-T Manager.