Exadata is the best database machine available to run every Oracle database workload. But many times, within Exadata proliferate a large number of test and development databases, that do not require the special features available with Exadata, the Storage cells and ASM.
One possibility is to move these large and less demanding databases to a storage layer that is also less expensive, ZFS is a perfect match, can be connected to Exadata, available to RAC databases, and connected via InfiniBand or RoCE for managing RMAN backups.
Its implementation is fast and simple, is fully explained on a few MOS documents:
This document describe the hardware deployment that is followed by Oracle Field Service enginneers
This document describe how to setup the Best Practices for Data Warehousing (DWH), for Online Transactional Processing (OLTP) Type Workloads; explain configuring
projects and shares on ZFS Storage and mounting shares on
Exadata and configuring the oranfstab.
Once these tasks have been completed you can create a test database on the ZFS mount points and query v$dnfs_servers, if you see the 2 ZFS heads reported as Dnfs servers then you can start moving your databases from ASM to ZFS.
If you need to use HCC, there is an additional step to run, setting up SNMP on the ZFS heads. for this please follow the instructions on this note. Once SNMP is setup on the heads you need to restart the databases to be able to use HCC: