In Oracle Database operations, the complexity of backup management is a significant challenge. By utilizing the Oracle Fast Recovery Area (FRA), you can automatically manage archived logs and RMAN backups, maximizing storage efficiency. This article provides a thorough explanation ranging from the mechanisms of the Fast Recovery Area to specific configuration procedures and troubleshooting methods for space depletion.
Conclusion: Shortest Steps for FRA Implementation
This is a “To-Do List” to enable FRA and begin operations.
- Secure Storage Location: Create a dedicated directory on a fast disk.
- Set Capacity Limit: Specify the maximum size using
DB_RECOVERY_FILE_DEST_SIZE. - Specify Storage Destination: Specify the path using
DB_RECOVERY_FILE_DEST. - Formulate Retention Policy: Set “how long to keep files” in RMAN.
- 1. What is the Fast Recovery Area (FRA)?
- 2. Types of Files Stored in FRA
- 3. Configuration and Enabling the Fast Recovery Area
- 4. Execution Example: Monitoring Usage Status
- 5. Troubleshooting: Insufficient Capacity (ORA-19809)
- 6. Operational Considerations and Security
- 7. FAQ (Frequently Asked Questions)
- 8. Summary
1. What is the Fast Recovery Area (FRA)?
The Fast Recovery Area (FRA) is a reserved storage area dedicated to Oracle Database for centrally managing files related to backup and recovery.
Mechanism and Benefits
Previously, archived logs and backup files required individual directory management. However, when FRA is enabled, Oracle determines “which files are no longer needed” and automatically deletes old (reclaimable) files when space becomes insufficient.
- Automation of Management: Automates file naming and deletion via Oracle Managed Files (OMF).
- Faster Recovery: Since necessary files are consolidated in one location, restoration via RMAN is smooth.
- Flashback Functionality: Required as the log storage destination for “Flashback Database,” which returns the database to a previous state.
2. Types of Files Stored in FRA
The following files are primarily stored in the FRA.
| File Type | Description |
| ARCHIVELOG | Logs indispensable for instance recovery and incomplete recovery. |
| RMAN Backups | Backup sets and image copies. |
| Control Files / REDO Logs | FRA can be specified as a multiplexing destination (Recommended). |
| Flashback Logs | Special logs for returning to a previous point in time. |
3. Configuration and Enabling the Fast Recovery Area
FRA settings can be changed online while the instance is running.
Prerequisites
- Privileges: A user with
SYSDBAprivileges (such asSYS). - Environment: In CDB/PDB environments, this is typically configured at the CDB level.
Procedure: Enabling FRA
The correct sequence is to set the maximum size limit first, then specify the path.
Setting the Maximum Size (e.g., 20GB)
-- Sets the maximum capacity of the FRA to 20GB
ALTER SYSTEM SET DB_RECOVERY_FILE_DEST_SIZE = 20G SCOPE=BOTH;
Setting the Destination Directory
-- Specifies the physical path for the FRA (the directory must already exist)
ALTER SYSTEM SET DB_RECOVERY_FILE_DEST = '/u01/app/oracle/fast_recovery_area' SCOPE=BOTH;
Configuration Verification Command
-- Displays the current setting values
SHOW PARAMETER DB_RECOVERY_FILE_DEST
SQL> SHOW PARAMETER DB_RECOVERY_FILE_DEST
NAME TYPE VALUE
--------------------------------- ------------------- -----------------------------------
db_recovery_file_dest string /u01/app/oracle/fast_recoveryare
db_recovery_file_dest_size big integer 20G
4. Execution Example: Monitoring Usage Status
FRA is not a “set it and forget it” feature. To prevent area exhaustion, monitor it regularly using the following views.
Check Overall Utilization
-- Displays the overall limit and current usage (in bytes) of the FRA
SELECT NAME, SPACE_LIMIT, SPACE_USED, SPACE_RECLAIMABLE FROM V$RECOVERY_FILE_DEST;
SQL> SELECT NAME, SPACE_LIMIT, SPACE_USED, SPACE_RECLAIMABLE FROM V$RECOVERY_FILE_DEST;
NAME SPACE_LIMIT SPACE_USED SPACE_RECLAIMABLE
---------------------------------------- ----------- ---------- -----------------
/u01/app/oracle/fast_recovery_are 2.1475E+10 0 0
SPACE_RECLAIMABLE: Capacity that can be deleted (reused) based on the retention policy.
Check Breakdown by File Type
-- Displays which files are consuming space as a percentage
SELECT FILE_TYPE, PERCENT_SPACE_USED, PERCENT_SPACE_RECLAIMABLE FROM V$FLASH_RECOVERY_AREA_USAGE;
SQL> SELECT FILE_TYPE, PERCENT_SPACE_USED, PERCENT_SPACE_RECLAIMABLE FROM V$FLASH_RECOVERY_AREA_USAGE;
FILE_TYPE PERCENT_SPACE_USED PERCENT_SPACE_RECLAIMABLE
------------------------------ ------------------ -------------------------
CONTROL FILE 0 0
REDO LOG 0 0
ARCHIVED LOG .3 0
BACKUP PIECE 23.96 15.97
IMAGE COPY 0 0
FLASHBACK LOG 0 0
FOREIGN ARCHIVED LOG 0 0
AUXILIARY DATAFILE COPY 0 0
8行が選択されました。
- SQL Intent: Analyze whether too many archived logs have accumulated or if backups are being deleted as expected.
5. Troubleshooting: Insufficient Capacity (ORA-19809)
If the FRA runs out of free space, archived logs cannot be output, and the database will hang (stop).
| Event | Cause | Action |
| ORA-19809 | Limit exceeded | Expand DB_RECOVERY_FILE_DEST_SIZE. |
| ORA-19815 | Warning message | Execute DELETE OBSOLETE in RMAN to delete unnecessary files. |
Recommended Action Flow
- Temporary Expansion:
ALTER SYSTEM SET DB_RECOVERY_FILE_DEST_SIZE = 30G; - Delete Unnecessary Backups (RMAN):
# Connect to RMAN and delete old backups
rman target /
RMAN> DELETE OBSOLETE;
6. Operational Considerations and Security
- Backup Retention Policy: The RMAN
CONFIGURE RETENTION POLICYand the FRA size are closely related. If you lengthen the retention period, you must increase the FRA size. - Prohibition of OS Command Deletion: Do not delete files within the FRA directly using the
rmcommand or similar. This causes inconsistency with Oracle’s management information. Always use RMAN. - Disk Separation: To prepare for physical disk failure, it is strongly recommended to place the FRA on a different physical disk from the data files.
7. FAQ (Frequently Asked Questions)
Q1. How much size should I estimate for the FRA?
A1. Generally, a guideline is “one full backup + one day’s worth of archived logs × number of retention days + alpha.”
Q2. Can I set a different FRA for each PDB?
A2. No. As of 19c, FRA is configured at the instance (CDB) level.
Q3. How do I disable the FRA?
A3. You can disable it by setting DB_RECOVERY_FILE_DEST to an empty string (''). However, ensure that a separate destination for archived logs is secured first.
8. Summary
- FRA is an Oracle-recommended storage area for automatically managing backup-related files.
- To enable it, perform the
DESTpath setting after theSIZEsetting. - Monitor free space regularly using the
V$RECOVERY_FILE_DESTview. - Insufficient capacity leads to database stoppage, so design it in conjunction with the RMAN retention policy.
This article is based on Oracle Database 19c (screens and default values may differ for other versions).
[reference]
Oracle Database Backup and Recovery Reference, 19c
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