Redo Logs Recovery

Recover Steps when Redo logs are Corrupted or Missed

1. One of the Redo Logs which is in Inactive State is corrupted or Removed
2. Active Redo Log is corrupted
3. All the Redo Logs are corrupted or Removed

In case if the Inactive Redo Logs were deleted just create the redo logs and clear the unarchived logfile.

Example

1. Removed the redo log at OS Level.
2. Switch the Log and we can see the errors in the alert log.
3. ALTER DATABASE CLEAR UNARCHIVED LOGFILE GROUP groupnumber;
4. Switch the logs.
5. Take Backup again.

Incase if ONLINE Redo Log is removed or corrupted or All the redo logs were removed

We need to restore the database and need to perform incomplete Recovery.

RMAN> restore database;

RMAN> recover database;

or

SQL> recover database until cancel;

SQL> alter database open resetlogs;