When you unmount a datastore, it remains intact, but can no longer be seen from the hosts that you specify. The datastore continues to appear on other hosts, where it remains mounted.
Do not perform any configuration operations that might result in I/O to the datastore while the unmounting is in progress.
Make sure that the datastore is not used by vSphere HA Heartbeating. vSphere HA Heartbeating does not prevent you from unmounting the datastore. However, if the datastore is used for heartbeating, unmounting it might cause the host to fail and restart any active virtual machine.
When appropriate, before unmounting datastores, make sure that the following prerequisites are met:
No virtual machines reside on the datastore.
Storage DRS does not manage the datastore.
Storage I/O Control is disabled for this datastore.
- Navigate to the datastore to unmount.
- Right-click the datastore and select Unmount Datastore.
- If the datastore is shared, select the hosts from which to unmount the datastore.
- Confirm that you want to unmount the datastore.
After you unmount a VMFS datastore from all hosts, the datastore is marked as inactive. If you unmount an NFS or a virtual volumes datastore from all hosts, the datastore disappears from the inventory. You can mount the unmounted VMFS datastore. To mount the NFS or virtual volumes datastore that has been removed from the inventory, use the New Datastore wizard.
What to do next
If you unmounted the VMFS datastore as a part of a storage removal procedure, you can now detach the storage device that is backing the datastore. See Detach Storage Devices.