When using “RMAN (Recovery Manager)” for Oracle Database backup operations, choosing where to store backup information is a critical decision. By using an Oracle Recovery Catalog, you can achieve long-term management exceeding the retention limits of control files and enable centralized management of multiple databases. This article explains the benefits of a Recovery Catalog and provides easy-to-follow steps for creation and registration, even for beginners.
- Conclusion: When You Should Use a Recovery Catalog
- Background and Basics: How the Recovery Catalog Works
- Steps to Create a Recovery Catalog
- Registration and Use of the Target Database
- Troubleshooting: Common ORA Errors
- Operational and Security Notes
- FAQ: Frequently Asked Questions Regarding Recovery Catalog Procedures
- Summary
Conclusion: When You Should Use a Recovery Catalog
In short, if you need to retain backup information for a long period (e.g., 365 days or more) or want to centrally manage multiple databases in one location, implementing a Recovery Catalog is strongly recommended.
To-Do List (Shortest Steps)
- Create a dedicated schema (user) in the catalog database and grant the necessary privileges.
- Connect to the catalog database via RMAN and execute
CREATE CATALOG. REGISTERthe target database into the Recovery Catalog.
Background and Basics: How the Recovery Catalog Works
Normally, RMAN backup history is recorded in the “Control File” of the target database itself. However, because control files are destined to be overwritten, old history eventually disappears. A “Recovery Catalog,” a dedicated external database, solves this issue.
Comparison: Control File Operation vs. Recovery Catalog Operation
| Comparison Item | Control File Operation (Default) | Recovery Catalog Operation |
| Information Storage | Target DB Control File | External dedicated database (Catalog DB) |
| Retention Period | Depends on CONTROL_FILE_RECORD_KEEP_TIME (Usually 7+ days) | Indefinite (Until manually deleted) |
| DB Total Loss Case | Requires restoration of the control file | Information can be referenced immediately from the catalog |
| Multi-DB Management | Managed separately for each DB | All DBs can be listed in a single catalog |
| Configuration Complexity | Simple (No additional DB required) | Requires operation and maintenance of the catalog DB |
Steps to Create a Recovery Catalog
When building a Recovery Catalog, two entities are involved: the “Catalog DB (the side that stores information)” and the “Target DB (the backup subject).”
Prerequisites
- Target OS: Oracle Linux / Windows (Common)
- Target Version: Oracle Database 19c
- The Catalog DB must be started separately and be accessible via network connection (SQL*Net).
1. Create the Catalog User
Log in to the Catalog DB and create the schema that will store the catalog information.
-- Execute on the Catalog DB side (Connect as SYS user, etc.)
-- It is advisable to avoid special characters like "@" in the password.
CREATE USER rcat_owner IDENTIFIED BY password_2026;
ALTER USER rcat_owner QUOTA UNLIMITED ON users;
GRANT CONNECT, RESOURCE, RECOVERY_CATALOG_OWNER TO rcat_owner;
Note: The
RECOVERY_CATALOG_OWNERrole covers all the privileges necessary for catalog management.
2. Initialize the Recovery Catalog
Start RMAN, connect to the Catalog DB, and create the catalog features (table groups).
# Connect from the OS command line
# rcat_owner: Catalog username, catdb: Connection identifier for the Catalog DB
rman catalog rcat_owner/password_2026@catdb
-- Execute at the RMAN prompt
-- Creates management tables within the catalog schema
RMAN> CREATE CATALOG;
Registration and Use of the Target Database
Registering the Target Database (Register)
Make the database intended for backup recognized by the catalog.
# Connect to both the Target DB and the Catalog DB
rman target / catalog rcat_owner/password_2026@catdb
-- Register the Target DB information in the catalog
RMAN> REGISTER DATABASE;
Caution: If the DB is recreated (DBID changes), it must be registered again.
Execution Example: Backup and Management
After registration, simply performing a backup as usual will automatically synchronize the information to the catalog.
-- Perform a full backup
RMAN> BACKUP DATABASE PLUS ARCHIVELOG;
-- Verify backup history (Retrieves information from the catalog)
RMAN> LIST BACKUP;
Intent: By executing the LIST command, you can display a list of past history from the Catalog DB even if the control file has been lost.
Troubleshooting: Common ORA Errors
| Error Code | Cause | Confirmation / Solution |
| ORA-12154 | The connection identifier to the Catalog DB cannot be resolved. | Check the tnsnames.ora settings. |
| RMAN-06004 | The Catalog DB is not open. | Check the status of the Catalog DB and MOUNT/OPEN it. |
| RMAN-06428 | The Recovery Catalog is not installed. | Execute the CREATE CATALOG command first. |
Operational and Security Notes
- Benefits and Risks:The benefit is management flexibility, but the disadvantage is that “the Catalog DB itself requires backups.” If the Catalog DB is corrupted, the latest backup information becomes unknown. Therefore, take measures such as enabling
CONTROLFILE AUTOBACKUPfor the Catalog DB itself. - Importance of Synchronization:While synchronization is usually automatic, if you manually manipulate the Target DB’s control file (such as deleting old logs via the OS), use the following command to ensure consistency:
RMAN> RESYNC CATALOG;
FAQ: Frequently Asked Questions Regarding Recovery Catalog Procedures
Q: Is recovery impossible without a Recovery Catalog?
A: No, recovery is possible using only the control file. However, in worst-case scenarios where the control file is completely lost and there is no autobackup, having a catalog reduces the difficulty of restoration.
Q: Can I create the Catalog DB on the same server?
A: It is technically possible, but as there is a risk of losing both in a server failure, the best practice is to place it on a separate server (or a different OCI instance, etc.).
Q: What happens to the catalog when upgrading from 19c to 23ai?
A: You can upgrade the catalog schema version using the UPGRADE CATALOG command.
Summary
- The Recovery Catalog is an “external database” that stores RMAN backup history.
- It is effective for long-term retention, centralized management of multiple DBs, and protection against control file corruption.
- Construction requires creating a dedicated user and running
CREATE CATALOG. - Do not forget to back up the Catalog DB itself.
This article explains based on Oracle Database 19c (screens and default values may differ for other versions).
[reference]
Recovery Catalog Views
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