This preface contains:
The following are changes in Oracle Database High Availability Overview for Oracle Database 12c Release 1 (12.1).
The following features are new in this release:
Global Data Services
Global Data Services applies the Oracle Real Application Clusters service model to sets of globally distributed, heterogeneous databases, providing load balancing and failover capabilities to database clouds with global services, which are services provided by multiple databases.
Oracle Flex Clusters and Oracle Flex ASM
Oracle Clusterware and Oracle Real Application Clusters can be configured in large clusters, called an Oracle Flex Cluster. Oracle Flex ASM decouples the Oracle ASM instance from the database servers. Oracle ASM instances may be run on separate physical servers (from the database servers). Any number of Oracle ASM servers can be clustered together to support a large set of databases.
A Data Guard far sync instance is a remote Data Guard destination that accepts redo from the primary database and then ships that redo to other members of the Data Guard configuration. A far sync instance manages a control file, receives redo into standby redo logs (SRLs), and archives those SRLs to local archived redo logs, but that is where the similarity with standbys ends. A far sync instance does not have user data files, cannot be opened for access, cannot run redo apply, and can never function in the primary role or be converted to any type of standby database.
Consolidation and multitenant architecture
The multitenant architecture feature enables an Oracle database to contain a portable set of schemas, objects, and related structures that appears logically to an application as a separate database.
Rolling upgrade using Oracle Active Data Guard
Rolling Upgrade using Oracle Active Data Guard provides new PL/SQL packages that automate much of the process of performing a database rolling upgrade using a physical standby database.
Oracle Active Data Guard enhancements
Support for Global Temporary Tables, replication of XMLType tables and columns, and enhanced security.
Application failover improvements
Application availability has been improved with the enhancement of Fast Application Notification, Oracle Service, and with the addition of Global Data Services, Application Continuity, and Transaction Guard.
The following are additional changes in the release:
Oracle MAA Reference Architectures
Oracle MAA reference architectures are applicable for a single database or application or for thousands of databases and applications, for DBaaS cloud or database consolidation. The entire contents of this document has been altered to highlight the MAA reference architectures.