Add-Cluster "Validate Cluster Creation Specification" fails with "Multiple portgroups found for transport type [MANAGEMENT, VSAN, VMOTION]" when sharing a VDS already used by a stretched vSAN cluster

Products

• VMware SDDC Manager / VCF Installer

Issue/Introduction

When attempting to share a Virtual Distributed Switch (VDS) from an existing stretched cluster during the creation of a new cluster, the operation fails at the "Validate Cluster Creation Specification" stage.

The following error message is observed: Multiple portgroups found for transport type [MANAGEMENT, VSAN, VMOTION]

This behavior occurs because VDS sharing logic assumes unique port group entries for any specific traffic type. Stretched clusters, by design, contain multiple availability zones with their own traffic types configured on distinct port groups, which triggers this validation error.

Environment

• Product: SDDC Manager 9.1.1.0
• Configuration: Stretched Cluster

Cause

Sharing a VDS is not supported for stretched clusters. Because stretched clusters utilize multiple availability zones with independent port groups for the same transport type, the system cannot verify uniqueness, causing the validation failure.

Resolution

The requested operation is not supported for stretched clusters. To proceed with sharing a VDS, use a configuration that supports unique port group entries per transport type.

1. Do not attempt to share a VDS amongst stretched clusters.
2. Perform the VDS sharing operation using a VDS sourced from a non-stretched cluster.

Additional Information

This KB article is specifically for use cases involving sharing a VDS during cluster creation where the source cluster is configured as a stretched cluster. The error message "Multiple portgroups found for transport type" may be triggered by other configuration issues in different contexts.