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. If you unmount an NFS datastore from all hosts, it disappears from the inventory.
Do not perform any configuration operations that might result in I/O to the datastore while the unmount is in progress.
For NFS or VMFS datastore, 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.
Before unmounting a VMFS datastores, make sure that the following prerequisites are met:
No virtual machines reside on the datastore.
The datastore is not managed by Storage DRS.
Storage I/O control is disabled for this datastore.
Browse to Datastores in the vSphere Web Client navigator. See Display Datastore Information in the vSphere Web Client.
- Right-click the datastore to unmount and select Unmount Datastore.
- If the datastore is shared, specify which hosts should no longer access the datastore.
- Confirm that you want to unmount the datastore.
After you unmount a VMFS datastore, the datastore is marked as inactive.
What to do next
If you unmounted the VMFS datastore as a part of an orderly storage removal procedure, you can now detach the storage device that is backing the datastore. See Detach Storage Devices.