The recovery process begins when you either suspect or discover a failure. You can discover failures in many ways, including error messages, alerts, trace files, and health checks. You can then use Data Recovery Advisor to gain information and advice about failures and repair them automatically.
This section describes a scenario in which you use Data Recovery Advisor to repair a corrupted block.
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Connect Oracle Recovery Manager (RMAN) to the target database as described in "Connecting to the Target Database Using RMAN."
In a multitenant environment, connect to the root as a common user with the SYSDBA
or SYSBACKUP
privilege.
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List all the failures know to the Data Recovery Advisor by running the following command:
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
Wherever possible, RMAN consolidates failures while displaying the result of the LIST FAILURE
command. For example, if a data file contains multiple block failures, the LIST FAILURE
command consolidates and displays the repair options.
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If you suspect that some failures that have not been automatically diagnosed by the database exist, then check for corrupt blocks and missing data files by using the following command:
VALIDATE DATABASE;
If a problem is detected during the validation, then RMAN triggers the execution of a failure assessment
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Determine repair options, both automatic and manual, by using the following command:
ADVISE FAILURE;
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Fix the failures by using the following command:
REPAIR FAILURE;
Automated repairs are performed by the Data Recovery Advisor. In certain cases, such as when no backups exist for a lost control file, the only repair option possible is the manual option.