After you create a Virtual Volumes datastore, it remains inaccessible.
Problem
The vSphere Client shows the datastore as inaccessible. You cannot use the datastore for virtual machine provisioning.
Cause
This problem might occur when you fail to configure protocol endpoints for the SCSI-based storage container that is mapped to the virtual datastore. Like traditional LUNs, SCSI protocol endpoints need to be configured so that an ESXi host can detect them.
Solution
Before creating virtual datastores for SCSI-based containers, make sure to configure protocol endpoints on the storage side.