Unable to add ESXi host to cluster in SDDC Manager due to vMotion and Management traffic overlap

Products

• VMware vCenter Server

Issue/Introduction

When attempting to add an ESXi host to a cluster via SDDC Manager, the operation fails during the VMK_CONFIGURATION_CHECK phase with an INVALID_VMK_TAG error. This issue occurs when Management and vMotion traffic types are mapped to the same distributed virtual port group, violating the VCF 9.x architecture guardrails that require a 1:1 separation of traffic types.

Environment

VMware Cloud Foundation (VCF) 9.x

Cause

The SDDC Manager network discovery service identifies a conflict in port group assignments. The Management and vMotion traffic types are currently mapped to the same distributed virtual port group. The VCF 9.x guardrails strictly require a 1:1 separation of traffic types, and the SDDC Manager database blocks the host addition to maintain compliance.

Resolution

1. Provision a dedicated port group for vMotion traffic that is distinct from the port group used for Management traffic.
2. On the target ESXi host, navigate to Networking > TCP/IP Configuration.
3. Assign the dedicated vMotion port group to a new or existing unique VMkernel adapter.
4. Ensure the vMotion traffic service is enabled only on this dedicated adapter.
5. Remove the vMotion service from the existing Management VMkernel adapter.
6. Trigger an inventory sync in SDDC Manager:
   • Navigate to SDDC Manager UI > Administration > Inventory.
   • Select the target domain and click Sync.
7. Retry the host addition workflow in the SDDC Manager UI.