vSAN services appear 'gone' or 'Not Configured' in vCenter after NSX DPG switch settings changes

Products

• VMware vSAN

Issue/Introduction

After applying desired state changes to your NSX Distributed Port Group settings, you might see vCenter reporting that vSAN is "not configured" or turned off. 

• vCenter cluster view prompts you to "configure vSAN."
• The vSAN datastore is visible and VMs are running fine.
• esxcli vsan cluster get on the hosts confirms the cluster is HEALTHY.

Environment

VMware vSAN 9.x

Cause

Updating NSX DPG switch settings can trigger a management-level desynchronization. vCenter essentially loses track of the vSAN configuration state, even though the storage layer at the host level is working perfectly.

Resolution

You need to force vCenter to re-read the state from the hosts.

1. Log in to the vSphere Client.
2. Select your Cluster, then go to Configure > vSAN > Services.
3. Click Configure vSAN.
4. Walk through the wizard. When you get to the Claim Disks screen, you will see your existing disks are already "In Use." That is correct.
5. Click through the rest of the wizard without changing anything else and hit Finish.

This forces vCenter to reach out to the hosts, see the existing configuration, and stop reporting the error.