Unable to add Witness node to vSAN stretch cluster with error "The witness host must not be part of a vSAN enabled cluster"

Products

• VMware vSAN

Issue/Introduction

Symptoms:

When attempting to select a witness host during vSAN stretch cluster configuration you get error "The witness host must not be part of a vSAN enabled cluster"

The witness is not in use by another cluster per vCenter and is not a Shared Witness

Running esxcli vsan cluster get on the witness shows it is in a cluster with no other hosts.

 

Cause

The witness has the vSAN service enabled already but is not joined to a cluster

Resolution

• On the witness host run the command esxcli vsan cluster leave
• Confirm the witness is no longer in a cluster by running esxcli vsan cluster get
• You can now select this witness in vCenter to add to the cluster.