Oracle Corporation introduced the Oracle Database Appliance in September 2011 as a member of Oracle's family of engineered systems (a group of combined hardware-and-software systems designed to provide a specific function — in this case, that of a database server). An ODA consists of a single-box device that contains the hardware, networking, storage and software needed to build a highly-available two-node clustered database server.
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History
Oracle Corporation introduced its first engineered database system, Oracle Exadata, in 2008. In 2011 it announced the Oracle Database Appliance. Smaller than Oracle Exadata, the Oracle Database Appliance contains less storage, memory and CPUs, and sells at a lower price-point. According to industry analysts, Oracle expects the Oracle Database Appliance to fill the gap in its product line beneath Oracle Exadata, targeting mid-market customers.
The platform proved very popular with DBAs, with enough support to launch a book about the systems.
Features
Despite its name, the Oracle Database Appliance supports more than database systems. Starting in release 2.5 (ODAV1) and 2.5.5 (ODA V2 X3-2), the appliance can be deployed using Oracle VM. This can allow an administrator to install not only the database, but also the application tier.
The Oracle Database Appliance also offers a pay-as-you grow model for Oracle licenses. This allows you to only license the CPU count you need, and not the entire capacity of the appliance. When virtualized this is supported for both the database and the application tier.
When the Oracle Database Appliance is connected to a ZS3 storage array, the DBA can leverage Hybrid Columnar Compression for data stored on the ZS3 array. This can enable not only tiered storage, but also compression ratios exceeding 20x.
Hardware
The first generation of the Oracle Database Appliance (ODA V1) is a two-node cluster in a single rack-mounted chassis. Inside the chassis are two servers, configured in a cluster, with shared storage. Each server contains two six-core processors, for a total of 12 cores per server. Each server also contains 96GB memory, six 1Gbit NICs, and two 10Gbit NICs. NICs are configured in an active/passive HA (bonding) configuration. Inside the appliance holds 4 x 73GB of shared SSD storage and 20 x 600GB of shared hard disk storage. The appliance contains redundant power supplies and cooling fans. Storage is configured at deploy time for either double mirroring (giving an overall capacity of 6TB data), or triple mirroring (yielding a capacity of 4TB data).
Following generations of the Oracle Database Appliance moved to a more flexible platform, utilizing Oracle X3-2 and X4-2 x86 servers and one or two SAS storage trays. Each compute node of the latest X4-based configuration includes 4 10GBaseT network ports, two 12-core Intel Xeon E5-2697 v2 processors, 256G ram and options 10gbe fiber connectivity. The system also can support up to two storage trays, each with 20 900G drives, and four 200G SSDs. This allows for 36T of raw disk space and for another 1.6T of raw SSDs. Single- and double-mirroring of disks is supported, for up to 18T of local data storage.
Software
The Oracle Database Appliance runs Oracle Linux, Oracle Grid Infrastructure for cluster and storage management, and a choice of Oracle Enterprise Edition, Oracle Real Application Clusters (RAC) One Node, or Oracle RAC. These latter two database products leverage the clustered nature of the hardware to database service failover in the event of a failure. Oracle also provides Oracle Clusterware for high-availability monitoring and cluster membership, and Oracle Automatic Storage Management for storage- and disk-management.
Administration
Oracle provides a deployment tool called the appliance manager to simplify the deployment and make it less time consuming. The vendor also provides special patch bundles for the database appliance, consisting of firmware, Linux OS, clustering, storage management, and database patches, which have been tested for compatibility.
Licensing
Customers can choose to license only a subset of the processor cores in the Oracle Database Appliance. This is done by disabling unnecessary processor cores in the BIOS, using a special interface. Cores can be enabled at a later time, allowing customers to increase the capacity of the appliance if required.
Criticism
The Oracle Database Appliance is a fixed configuration as described above. Customers cannot cluster multiple appliances together to create a larger cluster (beyond 2 servers), nor can they expand the internal disk storage of the system beyond the two storage trays. However, if a customer runs out of storage space, they can extend their storage to dNFS-attached storage. Currently, when leveraging an Oracle ZS3 array, the storage limit is approximately 3.5PB.