VM creation fails when selecting a Storage Policy that is not compatible with the Provider VDC's primary compute cluster

Products

• VMware Cloud Director

Issue/Introduction

• After adding a second resource pool/cluster into a Provider Virtual Datacenter (PVDC) in VMWare Cloud Director (VCD) you will be experiencing Virtual Machine (VM) placement problems.
• While creating VMs inside the Organization VDC (Org VDC) the placement engine always places the VM on the primary resource pool/cluster.
• If you try to force the VM creation onto the newly created resource pool by creating a new storage policy in vCenter, VCD states that the datastore cannot be used.
• The issue occurs for Flex Allocation model Org VDCs. 

Environment

VMware Cloud Director 10.6.1.1

Cause

The behavior you're experiencing with VM placement and the storage policy is related to how Cloud Director handles multiple independent resource pools/clusters. By default, the Cloud Director placement engine does not automatically load-balance across different datastores if the elasticity of the OVDC is not enabled. 

If elasticity of the OVDC is not enabled, VCD cannot decouple the tenant's virtual data center from physical cluster boundaries using the Workload Placement Engine and the hence the VM placement engine always places the VM in the primary resource pool. 

Resolution

To resolve the issue please enable elasticity for the particular OVDC we are looking for balancing the workload. To enable Elasticity please follow the below steps.

1. Click on Cloud Resources after login into the provider portal. 
2. Click on Organization VDCs.
3. Then click on the OVDC you are looking into enabling elasticity.
4. Click on Allocation for the OVDC.
5. Click Edit.
6. Enable Elasticity by click on the toggle.
7. Click Save.