When you configure Oracle Exadata Cloud@Customer, Oracle Automatic Storage Management (ASM) provisions the storage space inside the Exadata storage servers. By default, ASM creates the following disk groups:
- The DATA disk group stores Oracle Database data files.
- The RECO disk group stores the Fast Recovery Area (FRA), which is an area of storage where Oracle Database can create and manage various files that are related to backup and recovery.
Only on Exadata Database Service, you can optionally create the SPARSE disk group to support Exadata snapshots. If you create the SPARSE disk group, ASM allocates less space to the DATA and RECO disk groups.
Exadata Cloud@Customer platform customers also need to decide whether to allocate storage to perform local backups to your Exadata storage. If you choose this option, ASM allocates more space to the RECO disk group and less to the DATA disk group.
The usable storage capacity is the storage available for Oracle Database files after taking into account high-redundancy ASM mirroring (triple mirroring), which provides highly resilient database storage on all Exadata Cloud@Customer configurations. The usable storage capacity does not factor in the use of Exadata compression capabilities, which can increase the effective storage capacity.
The database servers connect to the Exadata storage servers through network fabric ports with active bonding. The Exadata infrastructure resides in your data center.
The diagram shows Exadata infrastructure with two database and three storage servers. Each storage server has flash storage and Exadata RDMA Memory (XRMEM).
Oracle manages the infrastructure through the management network, which connects the database and storage server hardware.
The client and backup networks provide access to your virtual machine (VM) clusters on the database servers. Oracle manages the infrastructure through the management network, which connects the database and storage server hardware.