Change the vSAN storage policy on VMs to save space

Products

• VMware vSAN

Issue/Introduction

• This article will help to understand as how much is the space consumption for different Storage policy in vSAN datastore.
  
  
• In certain situations there may be a need to convert the vSAN datastore for the Virtual machines to free up space on vSAN datastore.
  
  
• In vCenter UI, Cluster > Monitor > vSAN > Skyline health will report Disk capacity warning if the vSAN Cluster usage is above the threshold.

Environment

VMware vSAN (All Versions)

Resolution

• Create a storage policy that defines storage requirements for the VM and its virtual disks, if the required policy does not exist.
• Assign Storage Policies to Virtual Machines as per the requirement.

• Applying the RAID-0 policy will avoid the space overhead. However, the RAID-0 policy will not provide any protection for the data against the disk/host failure.

Note:

• VM storage policy conversion needs be done methodically instead of all at once to diminish the extra processing and to lower the amount of required overhead space.
• Ensure there is available space for the storage policy conversion prior to attempting the storage policy change.
• During the policy change until cutover to the new policy, both RAID layout (existing and new policy) will be active.

Additional Information

Using vSAN Policies 

Assign Storage Policies to Virtual Machines