3.9.2.1 Administer EDV Attachments
An Exascale Direct Volume (EDV) attachment can be used as a raw block storage device or to support a file system. EDV is the default and recommended volume attachment type for cases where clients want to use volumes within the Exadata RDMA Network Fabric. To implement Oracle Advanced Cluster File System (ACFS) on Exascale block volume storage, you must use an EDV attachment.