Resolving MRP Failure with ORA-10567 in Oracle Data Guard (Standby Database)
Introduction
In an Oracle Data Guard environment, the Managed Recovery Process (MRP) plays a critical role in applying redo logs from the primary database to the standby database. Any disruption in MRP can directly impact data synchronization and disaster recovery readiness.
This blog explains a real-time issue where the MRP process terminated unexpectedly with ORA-10567 and ORA-00600 errors, along with the root cause analysis and step-by-step recovery solution.
Real-World Scenario
During routine monitoring of a physical standby database, it was observed that the MRP process had stopped unexpectedly. As a result, redo logs were no longer being applied, causing a gap between the primary and standby databases.
Further investigation of the alert log revealed internal errors related to block corruption. Since this was a production standby environment, immediate action was required to restore synchronization and avoid potential data protection risks.
Issue Description
The following errors were observed in the standby database alert log:
ORA-00600: internal error code, arguments: [3020], [7], [768706], [30128834], [], [], [], [], [], [], [], []
ORA-10567: Redo is inconsistent with data block (file# 7, block# 768706, file offset is 2002272256 bytes)
ORA-10564: tablespace TBS02
ORA-01110: data file 7: 'F:\APP\ADMINISTRATOR\ORADATA\TBS\TBS02.DBF'
ORA-10561: block type 'TRANSACTION MANAGED DATA BLOCK'
Root Cause Analysis
The error clearly indicates a data block corruption in the standby database datafile.
- ORA-10567 → Redo does not match the data block
- ORA-00600 [3020] → Internal error triggered due to inconsistency
- Datafile 7 (TBS02) contains corrupted block
During redo apply, MRP attempts to apply changes to a corrupted block, which causes recovery to fail and terminate.
Solution
To resolve this issue, the corrupted datafile must be restored from the primary database and applied on the standby.
Step 1: Take Backup from Primary Database
Connect to RMAN on the primary database:
RMAN> rman target /
Take backup of the affected datafile:
RMAN> backup device type disk format 'F:\rman_backup_21\%U' datafile 7;
After the backup completes:
- Copy the backup pieces to the standby server
Step 2: Restore Datafile on Standby
On the standby database:
Start and mount the standby:
SQL> startup nomount;
SQL> alter database mount standby database;
Connect to RMAN:
RMAN> rman target /
Catalog the backup location:
RMAN> catalog start with 'F:\rman_backup_21\' noprompt;
Restore the corrupted datafile:
RMAN> restore datafile 7;
Exit RMAN:
RMAN> exit;
Step 3: Restart MRP
SQL> recover managed standby database disconnect from session;
Validation
After recovery:
- Verify MRP is running
- Check alert log for errors
- Monitor redo apply lag
Key Takeaways
- ORA-10567 indicates redo inconsistency due to block corruption
- MRP stops when encountering corrupted blocks
- Restoring affected datafile from primary resolves the issue
- Quick identification is critical to avoid data lag
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