Overview of Oracle RAC Database Administration
Oracle RAC database administration requires certain privileges and administrative tasks can vary depending on the deployment model.
The policy-managed database deployment option is desupported in Oracle AI Database 26ai.
Required Privileges for Oracle RAC Database Administration
Use the SYSRAC administrative privilege to manage Oracle RAC databases.
To increase security and further separate administrative duties, Oracle RAC database administrators manage Oracle RAC databases with the SYSRAC administrative privilege.
The SYSRAC administrative privilege is the default mode of connecting to the database by the Oracle Clusterware agent on behalf of Oracle RAC utilities, such as SRVCTL.
Related Topics
Oracle RAC Database Deployment Models
Starting with Oracle Database 21c, there is a single, merged management style for Oracle RAC databases.
Note:
The policy-managed database deployment option is desupported in Oracle AI Database 26ai.
Prior to Oracle Database 21c, Oracle RAC databases support two different management styles and deployment models: administrator-managed deployment and policy-managed deployment.
Administrator-managed deployment requires that you statically configure each database instance to run on a specific node in the cluster. This deployment also requires that you configure database services to run on specific instances that belong to a particular database using the preferred and available designation.
Policy-managed deployment is based on server pools. In this deployment, database services run within a server pool as singleton or uniform across all of the servers in the server pool. Databases are deployed in one or more server pools and the size of the server pools determine the number of database instances in the deployment.
Starting with Oracle Database 21c, the two management styles are merged into a single deployment model that combines the best features of each model. The administrator-managed database deployment style now has additional capabilities that were previously available only in policy-managed databases. These enhancements result in a new, converged deployment style. To use the merged database management style, you must have a Container Database (CDB) with at least one Pluggable Database (PDB).
You manage the merged database deployment model using the same commands and utilities (such as SRVCTL, Oracle DBCA, or Oracle Enterprise Manager) as before. All commands and utilities, except for the policy-management specific commands such as srvpool commands, maintain backward compatibility to support the management of databases prior to Oracle Database 21c.
The merged database management style simplifies management of dynamic systems. The clusters and databases can expand or shrink as requirements change. The Oracle home software must be installed on every node in the cluster.
Benefits of the merged management style
The PDBs in the cluster database are available on all nodes, or a subset of the nodes, based on the cardinality setting for the PDB. The cardinality of a PDB governs the number of nodes where a PDB can run at the same time. If you use a number for cardinality instead of ALL, then the instances in which the PDBs are opened depend on the resources available to each instance.
A database instance is started on every server in the cluster that hosts a PDB. If you are using Oracle Automatic Storage Management (Oracle ASM) with Oracle Managed Files for your database storage, then, when an instance starts and there is no redo thread available, Oracle RAC automatically enables one and creates the required redo log files and undo tablespace.
Clients can connect to a PDB using the same SCAN-based connect string irrespective of which servers the PDBs are running on at the time.