Adding a new cluster to an existing domain fails with "ESXI_HOST_ALREADY_HAS_VSAN_ENABLED".

Products

• VMware SDDC Manager

Issue/Introduction

• Adding a new cluster to an existing domain fails with "ESXI_HOST_ALREADY_HAS_VSAN_ENABLED".
• Error in /var/log/vmware/vcf/domainmanager/domainmanager.log

  yyyy-mm-ddT16:20:39.271+0000 INFO  [vcf_dm,6482b402bd8e451a,80c7] [c.v.e.s.c.c.v.vsan.VsanManagerBase,dm-exec-7]  Checking if vSAN is enabled on the vSAN system of test-cluster-esxi1.example.com
  yyyy-mm-ddT16:20:39.276+0000 DEBUG [vcf_dm,6482b402bd8e451a,80c7] [c.v.v.h.s.v.HostValidatorUtil,dm-exec-7]  ESXi Host test-cluster-esxi1.example.com has vSAN enabled. 
  yyyy-mm-ddT16:20:39.283+0000 ERROR [vcf_dm,6482b402bd8e451a,80c7] [c.v.v.c.f.a.ValidateClusterSpecAction,dm-exec-7]  Cluster Spec validation failed with errors [ESXI_HOST_ALREADY_HAS_VSAN_ENABLED, ESXI_HOST_ALREADY_HAS_VSAN_ENABLED, ESXI_HOST_ALREADY_HAS_VSAN_ENABLED, ESXI_HOST_ALREADY
  _HAS_VSAN_ENABLED, ESXI_HOST_ALREADY_HAS_VSAN_ENABLED, ESXI_HOST_ALREADY_HAS_VSAN_ENABLED]

Environment

VMware Cloud Foundation 4.5

Cause

• This issue occurs if the vSAN is enabled on the hosts 
• Due to remnants of previous vSAN data-stores.

Resolution

1. Check if the host is part of any vSAN cluster by running the below command.

   esxcli vsan cluster get

2. Decommission the hosts from a vSAN Cluster. 

   esxcli vsan cluster leave

   Refer - Permanently Decommissioning a node from a vSAN Cluster

3. Follow the same steps for the remaining hosts.