3.2.1 About Oracle Exadata Extended (XT) Storage Servers

Oracle Exadata Extended (XT) Storage Servers help you extend the operational and management benefits of Exadata Database Machine to rarely accessed data that must be kept online.

Each XT storage server includes twelve high-capacity disk drives, with the overall hardware specification optimized to reduce cost. Oracle Exadata System Software licensing is optional for XT storage servers, with some software features disabled unless licensed. However, Hybrid Columnar Compression is included and does not require Oracle Exadata System Software licensing.

XT storage servers use the same RDMA Network Fabric as other servers in your Oracle Exadata Rack. They add storage capacity while remaining transparent to applications and SQL. You can continue to use the same security, encryption, and operational model as with your other Exadata storage servers.

You can add XT storage servers to existing Oracle Exadata Rack configurations. The initial deployment requires at least two XT storage servers. However, for high redundancy, you need at least three XT storage servers. After the initial setup, you can add more XT storage servers as needed. XT storage servers follow the same placement patterns as High Capacity (HC) and Extreme Flash (EF) storage servers.

After you add XT storage servers to your rack, you can create new Oracle ASM disk groups to use the additional storage. For XT storage, the default disk group name is XTND, but you can choose a different name.

Beginning with Exadata Storage Server X11M XT, you can also build Oracle Exadata Exascale storage pools using XT storage. However, earlier XT storage server models are not permitted with Exascale.

In general, an Oracle ASM disk group or Exascale storage pool must not combine storage from different server types. Therefore, you cannot add XT storage to existing disk groups or storage pools that use non-XT storage.

XT storage servers provide fully integrated storage for Oracle Database. You can use XT storage with database features such as Oracle Partitioning and Oracle Advanced Compression.