In the VMware Host Client, you can delete namespaces that were not created by ESXi, but by an OS that was previously installed on the host machine.
- Put the host in maintenance mode.
- Back up the content of the namespace if you might need that content at a later time.
- In the VMware Host Client, click Storage.
- Under the Persistent Memory tab, click Namespaces.
- (Optional) In the list of namespaces, check the State column to determine which namespaces ESXi currently uses.
To free up space, you must delete namespaces whose state is In Use.
- Select a namespace and click the Delete icon.
Important: Deleting a namespace frees up space on the datastore, but you can use the free space only after you reboot the host.
- Click the Reboot host icon to reboot the host.