You can remove selected devices from the disk group or an entire disk group.
About this task
Because removing unprotected devices might be disruptive for the vSAN datastore and virtual machines in the datastore, avoid removing devices or disk groups.
Typically, you delete devices or disk groups from vSAN when you are upgrading a device or replacing a failed device, or when you must remove a cache device. Other vSphere storage features can use any flash-based device that you remove from the vSAN cluster.
Deleting a disk group permanently deletes the disk membership and the data stored on the devices.
Removing one flash cache device or all capacity devices from a disk group removes the entire disk group.
Evacuating data from devices or disk groups might result in the temporary noncompliance of virtual machine storage policies.
Prerequisites
You can either place the vSAN host in maintenance mode by selecting the Evacuate all data option or by selecting Ensure data accessibility when deleting a device or a disk group. If you select No data evacuation from the drop-down menu, your data might be at risk if a failure occurs during evacuation.