Mechanism, Configuration, and Best Practices with Diagrams
When operating Oracle Database in a production environment, reliable backup and recovery mechanisms are essential.
At the core of these operations is the Fast Recovery Area (FRA).
In this article, we explain what FRA is, its purpose, stored files, configuration parameters, recommended architecture, and key considerations, all with easy-to-understand full-width ASCII diagrams.
- 1. What is the Fast Recovery Area (FRA)?
- 2. What files are stored in FRA?
- 3. FRA Structure (Diagram)
- 4. Benefits of FRA
- 5. FRA Configuration Parameters
- 6. How to Check FRA Usage
- 7. Why You Should Separate FRA from Data Files (Best Practice)
- 8. Common Issues with FRA and Solutions
- 9. Risks of Not Using FRA
- ✅ Summary: FRA is the Foundation of Safe Oracle Operation
1. What is the Fast Recovery Area (FRA)?
The Fast Recovery Area is a dedicated storage area where Oracle automatically stores and manages all files needed for backup and recovery.
Introduced in Oracle 10g, it is now a standard component of modern Oracle backup strategies.
◆ In short, what does FRA do?
A dedicated Oracle-managed area that stores all recovery- and backup-related files in one place.
2. What files are stored in FRA?
Below are the typical file types stored in the FRA:
+--------------------------+---------------------------------------------+
| File Type | Description |
+--------------------------+---------------------------------------------+
| Archived Redo Logs | Historical redo log files for recovery |
| Auto Backup Files | spfile and control file backups |
| RMAN Backup Sets | Datafile backups created by RMAN |
| Flashback Logs | Information for flashback operations |
| Temporary Redo Logs | Used in some configurations temporarily |
+--------------------------+---------------------------------------------+
3. FRA Structure (Diagram)
+---------------------------------------------------------+
| Fast Recovery Area (FRA) |
| +------------------+ +----------------------------+ |
| | Archived Redo Log| | RMAN Backup Sets | |
| +------------------+ +----------------------------+ |
| +------------------+ +----------------------------+ |
| | Flashback Logs | | Auto Backup Files | |
| +------------------+ +----------------------------+ |
+---------------------------------------------------------+
4. Benefits of FRA
| Benefit | Description |
|---|---|
| ✅ Automatic Management | Oracle automatically deletes obsolete files to manage space |
| ✅ Centralized Storage | Easy to manage since all backup-related files are in one place |
| ✅ Works with RMAN | RMAN automatically recognizes and uses the FRA |
| ✅ Flashback Support | Flashback logs are also stored in FRA |
5. FRA Configuration Parameters
To enable FRA, set the following two initialization parameters:
DB_RECOVERY_FILE_DEST → Specifies the FRA directory path
DB_RECOVERY_FILE_DEST_SIZE → Specifies the maximum size (in bytes)
▶ Example (with spfile):
ALTER SYSTEM SET DB_RECOVERY_FILE_DEST='/u02/app/oracle/fast_recovery_area' SCOPE=BOTH;
ALTER SYSTEM SET DB_RECOVERY_FILE_DEST_SIZE=20G SCOPE=BOTH;
6. How to Check FRA Usage
You can check FRA usage using the following view:
SELECT * FROM V$RECOVERY_FILE_DEST;
| Column Name | Description |
|---|---|
| SPACE_LIMIT | Maximum size (in bytes) |
| SPACE_USED | Current usage (in bytes) |
| SPACE_RECLAIMABLE | Space that can be reclaimed |
| NUMBER_OF_FILES | Number of files currently stored |
7. Why You Should Separate FRA from Data Files (Best Practice)
+------------------------------+-------------------------------+
| Data File Disk | FRA Disk |
+------------------------------+-------------------------------+
| ・Data files | ・Archived redo logs |
| ・Online redo logs | ・RMAN backup sets |
| ・TEMP tablespace files | ・Control file autobackups |
+------------------------------+-------------------------------+
Reason 1: Prevent I/O contention
→ Separate disks prevent performance issues during backup or archiving.
Reason 2: Better recovery in case of disk failure
→ If the datafile disk fails, you can still recover using backups in the FRA.
Reason 3: Protect against sudden storage increase
→ FRA may grow rapidly due to large amounts of archived logs or backups.
8. Common Issues with FRA and Solutions
| Issue | Solution |
|---|---|
| FRA running out of space | Increase size or run DELETE OBSOLETE in RMAN |
| Archived logs keep piling up | Move logs to external storage or adjust retention policy |
| Database stops due to full FRA | Monitor and set up alerts to avoid disk full issues |
9. Risks of Not Using FRA
- Files like backups and logs may be scattered, making management harder
- No automatic deletion leads to high risk of disk full errors
- Flashback and RMAN functionality becomes harder to manage
✅ Summary: FRA is the Foundation of Safe Oracle Operation
The Fast Recovery Area (FRA) is a vital component
that supports reliable, efficient Oracle backup and recovery.
- Always place FRA on a separate disk for performance and safety
- Monitor usage regularly to avoid unexpected outages
- Use FRA to make the most of RMAN and flashback features
[reference]
9.2.7 Fast Recovery Area
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