Health alarm is flagged detected thick-provisioned

Products

• VMware vSAN

Issue/Introduction

• If the VMs are in "Thick provisioning", vSAN datastore usage will be higher.
  
  
• vSAN online health check reports a warning for thick disks provisioned on virtual machines.
  
  
• This health alarm is flagged because vSAN has detected thick-provisioned VMs even though the applied vSAN storage policy has object space reservation set to 0 (Thin-provisioned). It is
  Recommended to reclaim the underlying storage from 'Thick' to 'Thin', which will improve storage utilization.
  
  
• This health alarm will not check VMs deployed by ESX Agent Manager (EAM), as most of the VMs deployed are thick-provisioned by default or VMs with disabled tasks (vm.disabledMethod), for example, NSX Controllers
   

Environment

7.0
7.0u3
8.0

8.0u3

Cause

This may be caused by the VMs being backed up from a SAN and restored to vSAN, regular storage vMotion shall always provision VMs with thin disks.

Resolution

Apply a cloned vSAN policy 

1. Click "Policies and Profiles" and select “VM Storage Policies.”
   Clone VM Storage Policy.
   
   
2. Apply the Cloned policy to the VM with thick-provisioned disks.
   

   Right-click on the VM in the vSphere Web Client navigator and select "Edit Settings"

3. Navigate to VM Storage Policies:
   In the Edit Settings dialog, locate and select the "VM Storage Policies" tab

4. Edit the storage policy:
   Select the cloned policy from the dropdown list and click "Apply to All". 
   
   
5. Reapply the <current policy>, such as the "vSAN default policy", back to the VM. 

Additional Information