RAC Improvements Since 2003

[sukishan]

Evolution of the GridWhile 9i enabled "islands" of RAC instances, 10g pulls those islands together into an interconnected grid. Through a concept called "services," Oracle enables any node to be allocated to any service and for the databases to share capacity, including spare capacity. Although Oracle defines a service as a RAC database, its vision is that the service will encompass all tiers of the application architecture, not just the database tier.

Clusterware on All Platforms
In 9i, Oracle Clusterware was only available on Windows and Linux. With 10g, it extended the technology to its other platforms. In 2003, Oracle acquired TruCluster software assets, which are a base for Oracle's Clusterware implementation. Therefore, customers that want a single-instance database with failover, rather than RAC, do not need to use third-party cluster software. However, for Unix platforms, customers can still implement their third-party clustering software if they choose to. For Windows and Linux, however, Oracle only supports its own clusterware with RAC.