Oracle Recovery Manager (RMAN) is a cornerstone component of Oracle Database, serving as the primary tool for backup and recovery operations. Throughout its versions, Oracle has continuously enhanced RMAN to address the evolving needs of database administration. Here, we examine the progressive enhancements and changes from Oracle Database 11g to Oracle Database 19c.
In Oracle Database 11g, RMAN already provided a comprehensive set of features for efficient data protection. It offered capabilities such as block-level corruption detection during backup and recovery, tablespace point-in-time recovery, and optimized RMAN backups using change tracking. While robust, there were areas earmarked for improvement and optimization.
Transitioning to Oracle Database 19c, RMAN has been significantly augmented with advanced features and improvements to further streamline backup and recovery processes:
Multitenant Database Support:
Oracle 19c introduced full-fledged support for multitenant databases, allowing RMAN to perform backup and recovery operations at both the container database (CDB) and pluggable databases (PDBs) levels. This enhancement greatly simplified backup strategies for complex multitenant environments.
Recovery Catalog Improvements:
The recovery catalog schema in Oracle 19c has been upgraded to support new features of the database engine. RMAN’s recovery catalog now includes enhanced metadata tracking for PDBs, providing a more granular level of control and recovery.
Advanced Compression Algorithms:
RMAN in Oracle 19c utilizes newer, more efficient compression algorithms to reduce the size of backups, optimize storage utilization, and reduce network bandwidth requirements for backup data transfers.
Improved Diagnostics and Reporting:
Enhanced reporting features in Oracle 19c provide DBAs with more detailed insights into backup and recovery operations, including improved visibility into the progress of long-running jobs.
Automated Database Duplication:
While 11g introduced the ability to duplicate a database from an active database, 19c expanded this capability by automating the process, reducing the amount of manual intervention required and accelerating the cloning process.
Oracle 19c's RMAN has strengthened backup optimization to skip redundant copies of data files and archived logs, ensuring only the necessary data is backed up and thus saving valuable time and storage resources.
Improved Handling of Very Large Files:
Acknowledging the trend towards ever-increasing data file sizes, RMAN in Oracle 19c has been optimized to handle very large files more efficiently, catering to the demands of modern data warehouses and big data applications.
Persistent Configuration Settings:
Configuration settings for RMAN are now persistent across RMAN sessions in Oracle 19c, making it easier to maintain consistent backup and recovery policies without the need to reapply configurations.
These improvements reflect Oracle’s commitment to providing robust tools for database management. Oracle 19c’s RMAN enhancements are designed not only to keep pace with the database’s new features but also to provide DBAs with a more powerful, efficient, and user-friendly experience in their critical backup and recovery operations.
Features and enhancements of Recovery Manager
So far, this course has introduced you to several new features of Recovery Manager (RMAN), the replacement of Enterprise Backup Manager that was used within Oracle7. To clarify, the actual backup and recovery of the Oracle database is done by the Oracle database server, and not done by RMAN.
RMAN is simply an interface to get the various aspects of backup and recovery done.
This module discusses some of the new features of RMAN, using Oracle Enterprise Manager and Recovery Manager since they are tightly integrated.
RMAN New Features for Oracle Database 11g Release 2 included Automatic Block Repair
Allows corrupt blocks on the primary database to be automatically repaired from physical standby database, as they are detected.
In-line and transparent. User sees brief wait from query on corrupt block while it is being repaired.
Can also be performed on-demand via RECOVER command
Requires Active Data Guard (real-time query on physical standby database).
When you complete this module, you will be able to:
Explain the new features of RMAN
Create a recovery catalog
Create and run a backup script in RMAN
Describe the new feature of specifying a character setfor a control file.
Recover a failed database by using the line mode of RMAN
Recover a failed database by using the RMAN GUI
Character set: A character set defines the language character set in which the data within a database is stored.
The next lesson starts up Recovery Manager and explores its features.
Control file: The control file is created and maintained by Oracle. It contains information about the physical locations of all files associated with the database as well as its logical information such as, the different tablespaces within a database as well as the character set information.