REPAIR FAILURE

Purpose

Use the REPAIR FAILURE command to repair database failures identified by the Data Recovery Advisor.

The recommended workflow is to run LIST FAILURE to display failures, ADVISE FAILURE to display repair options, and REPAIR FAILURE to fix the failures.

Prerequisites

The target database instance must be started. The database must be a single-instance database and must not be a physical standby database.

Make sure that at most one RMAN session is running the REPAIR FAILURE command. The only exception is REPAIR FAILURE ... PREVIEW, which is permitted in concurrent RMAN sessions.

To perform an automated repair, the Data Recovery Advisor may require specific backups and archived redo log files. If the files needed for recovery are not available, then the recovery will not be possible.

Usage Notes

Repairs are consolidated whenever possible so that a single repair can fix multiple failures. Be advised that REPAIR FAILURE requires you to explicitly run ADVISE FAILURE in the current session in order to successfully repair each of the identified failures. You typically iterate through a REPAIR session with the following commands:

REPAIR FAILURE;
LIST FAILURE;
ADVISE FAILURE;
REPAIR FAILURE;

RMAN always verifies that failures are still relevant and automatically closes fixed failures. RMAN does not attempt to repair a failure that has already been fixed, nor does it repair a failure that is obsolete because new failures have been introduced since ADVISE FAILURE was run.

By default, REPAIR FAILURE prompts for confirmation before it begins executing. After executing a repair, RMAN reevaluates all existing failures on the chance that they may also have been fixed.

Oracle RAC and Data Recovery Advisor

If a data failure brings down all instances of an Oracle RAC database, then you can mount the database in single-instance mode and use Data Recovery Advisor to detect and repair control file, SYSTEM datafile, and dictionary failures. You can also initiate health checks to test other database components for data failures. This approach will not detect data failures that are local to other cluster instances, for example, an inaccessible datafile.

Syntax

repair::=

Description of the illustration repair.gif

Semantics

repair

Syntax Element	Description
`REPAIR FAILURE`	Repairs failures recorded in the Automated Diagnostic Repository. If you execute `REPAIR FAILURE` with no other command options, then RMAN uses the first repair option of the most recent `ADVISE FAILURE` command in the current session. The command performs an implicit `ADVISE FAILURE` if this command has not yet been executed in the current session.
`USING ADVISE OPTION` `integer`	Specifies a repair option by its option number (not its failure number). You can obtain repair option numbers from the `ADVISE FAILURE` command.
`NOPROMPT`	Suppresses the confirmation prompt. This is the default option if you run `REPAIR FAILURE` in a command file.
`PREVIEW`	Does not make any repairs and generates a script with all repair actions and comments. By default the script is displayed to standard output. You can use the `SPOOL` command to write the script to an editable file (see Example 3-12).

Examples

Example 3-11 Repairing Failures

This example repairs all failures known to the Recovery Data Advisor. The example repairs two failures: missing datafiles and a datafile with corrupt blocks. After the recovery, RMAN asks whether it should open the database (user-entered text is in bold).

RMAN> LIST FAILURE;
 
List of Database Failures
=========================
 
Failure ID Priority Status    Time Detected Summary
---------- -------- --------- ------------- -------
142        HIGH     OPEN      23-APR-07     One or more non-system datafiles are missing
101        HIGH     OPEN      23-APR-07     Datafile 1: '/disk1/oradata/prod/system01.dbf' 
                                            contains one or more corrupt blocks
 
RMAN> ADVISE FAILURE;
 
List of Database Failures
=========================
 
Failure ID Priority Status    Time Detected Summary
---------- -------- --------- ------------- -------
142        HIGH     OPEN      23-APR-07     One or more non-system datafiles 
                                            are missing
101        HIGH     OPEN      23-APR-07     Datafile 1: '/disk1/oradata/prod/system01.dbf' 
                                            contains one or more corrupt blocks
 
analyzing automatic repair options; this may take some time
using channel ORA_DISK_1
analyzing automatic repair options complete
 
Mandatory Manual Actions
========================
no manual actions available
 
Optional Manual Actions
=======================
1. If file /disk1/oradata/prod/users01.dbf was unintentionally renamed or moved, restore it
 
Automated Repair Options
========================
Option Repair Description
------ ------------------
1      Restore and recover datafile 28; Perform block media recovery of 
       block 56416 in file 1
  Strategy: The repair includes complete media recovery with no data loss
  Repair script: /disk1/oracle/log/diag/rdbms/prod/prod/hm/reco_660500184.hm

RMAN> REPAIR FAILURE;
 
Strategy: The repair includes complete media recovery with no data loss
Repair script: /disk1/oracle/log/diag/rdbms/prod/prod/hm/reco_475549922.hm
contents of repair script:
   # restore and recover datafile
   sql 'alter database datafile 28 offline';
   restore datafile 28;
   recover datafile 28;
   sql 'alter database datafile 28 online';
   # block media recovery
   recover datafile 1 block 56416;
 
Do you really want to execute the above repair (enter YES or NO)? YES
executing repair script
 
sql statement: alter database datafile 28 offline
 
Starting restore at 23-APR-07
using channel ORA_DISK_1
 
channel ORA_DISK_1: starting datafile backup set restore
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_DISK_1: restoring datafile 00028 to /disk1/oradata/prod/users01.dbf
channel ORA_DISK_1: reading from backup piece /disk2/PROD/backupset/2007_04_18/o1_mf_nnndf_TAG20070418T182042_32fjzd3z_.bkp
channel ORA_DISK_1: piece handle=/disk2/PROD/backupset/2007_04_18/o1_mf_nnndf_TAG20070418T182042_32fjzd3z_.bkp tag=TAG20070418T182042
channel ORA_DISK_1: restored backup piece 1
channel ORA_DISK_1: restore complete, elapsed time: 00:00:03
Finished restore at 23-APR-07
 
Starting recover at 23-APR-07
using channel ORA_DISK_1
 
starting media recovery
media recovery complete, elapsed time: 00:00:01
 
Finished recover at 23-APR-07
 
sql statement: alter database datafile 28 online
 
Starting recover at 23-APR-07
using channel ORA_DISK_1
searching flashback logs for block images until SCN 429690
finished flashback log search, restored 1 blocks
 
starting media recovery
media recovery complete, elapsed time: 00:00:03
 
Finished recover at 23-APR-07
repair failure complete

Example 3-12 Previewing a Repair

The following example previews a repair of the first repair option of the most recent ADVISE FAILURE command in the current session. Note that the sample output for the LIST FAILURE and ADVISE FAILURE commands is not shown in the example.

RMAN> LIST FAILURE;
.
.
.
RMAN> ADVISE FAILURE;
.
.
.
RMAN> REPAIR FAILURE PREVIEW;

Strategy: The repair includes complete media recovery with no data loss
Repair script: /disk1/oracle/log/diag/rdbms/prod/prod/hm/reco_3200987003.hm

contents of repair script:
   # block media recovery
   recover datafile 1 block 56416;

You can use SPOOL in conjunction with REPAIR FAILURE ... PREVIEW to write a repair script to a file. You can then edit this script and execute it manually. The following example spools a log a repair preview to /tmp/repaircmd.dat.

RMAN> SPOOL LOG TO '/tmp/repaircmd.dat';
RMAN> REPAIR FAILURE PREVIEW;
RMAN> SPOOL LOG OFF;