A High Availability Cluster and the Foundation for Oracle RAC

A High Availability Cluster and the Foundation for Oracle RAC

Oracle Clusterware is a portable cluster software that allows clustering of independent servers so that they cooperate as a single system. Oracle Clusterware was first released with Oracle Database 10g Release 1 as the required cluster technology for the Oracle multi-instance database, Oracle Real Application Clusters (RAC).

What's New in Oracle Clusterware

Technical Brief: What's New in Oracle Clusterware (PDF)

Technical Brief: What's New in Oracle Clusterware (PDF)

Video: Oracle Clusterware Introduction

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Oracle Clusterware, grouped with Oracle Automatic Storage Management (ASM) as  Oracle Grid Infrastructure, is the integrated foundation for Oracle Real Application Clusters and the high availability and resource management framework for all applications on any major platform supported for Oracle RAC. Over the past 10 or more years, Oracle Clusterware 11g and then Oracle Clusterware 12c and Oracle Clusterware 18c provide a high quality platform that enabled high availability and scalability for RAC databases and applications. Now, Oracle Clusterware 19c builds on this innovative technology by further simplifying cluster deployments and improving the overall ease of use. Oracle Clusterware is leveraged in the cloud in order to provide enterprise-class resiliency where required and dynamic as well as online allocation of compute resources where needed, when needed.

New in Oracle Clusterware

Oracle Clusterware 19c continues the purpose of previous releases in simplifying deployments and enhancing the user experience.  Primary in these is the removal of Leaf Nodes from the Flex Cluster architecture. Instead, Oracle Clusterware 19c will provide support for read-moslty database instance and application-only cluster nodes on the standard Hub nodes, thus simplifying both the deployment and operational management of the clusters. This will be particularly beneficial in the cases of mixed cluster workloads and consolidated database systems.

With Oracle Cluserware 18c, we introduced significant enhancements and new features that focused primarily on ease of use and the reduction of operating overhead. A primary benefit was the reduction in the number of IP-addresses required for deployments provided by removing the need for Node VIP's and utilizing a Shared SCAN VIP setup amongst many clusters. Of special note was the addition of the capability to patch the GI stack without affecting the local RAC database instance, thus not impacting the users of that database. Significant enhancements were also made for the Cluster Domains (added in Oracle 12c Release 2), adding the ability to convert Standalone Clusters to Member Clusters and the provisioning of local ACFS file systems on Member Clusters using the remote ASM storage services. In addition is the introduction of Cross-Cluster Dependency Protocol Proxies, enabling Clusterware resource dependency management across clusters.

Oracle Grid Infrastructure (Bundled) Agents

Oracle Grid Infrastructure provides the necessary components to manage high availability (HA) for any business critical application. HA in consolidated environments is no longer simple active/standby failover. These environments require run-time workload management that guarantees resource allocation when required. Oracle Grid Infrastructure Agents enable workload management and HA for Oracle applications (currently available for Siebel, Oracle E-Business Suite, Oracle GoldenGate, Peoplesoft, JD Edwards, WebLogic as well as Apache and MySQL). With Oracle Grid Infrastructure 11g Release 2 ( and later), the only delivery method for agents was "standalone"; supported on AIX, Solaris, Linux and Windows.

The standalone deployment model offers greater flexibility in choosing the agent home directory structure and for subsequent agent upgrades. The standalone deployment is the preferred installation model and will continue to be available, though support for the bundled agents (those 'bundled' with the release of the Grid Infrastructure software) will continue.

Oracle RAC Family of Solutions

The Oracle RAC Family of Solutions refers to the collection of products and features that licensed Oracle RAC or Oracle RAC One Node customers can use free of additional charge. Each solution either enhances or complements the core Oracle RAC offering by ensuring better high availability and scalability or by automating and simplifying day-to-day operation. Learn more about these valuable enhancements by following the link for each solution in the graphic below. To learn more about Oracle Clusterware, follow the link on the bottom of the page.

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