Missing logs, Out-of SYNC (Physical standby)

Auto Sync, some time auto sync not happens result of which standby lag behinds, some steps below can make standby to sync with primary:


1.

On standby check

1. Select process,status from v$managed_standby; and this query should return mrp as process, if mrp is not coming means recovery process Is not active.

2. Try recover managed standby database cancel; and again try recover managed standby database using current logfile disconnect from session.

At primary check :

3. select current_scn from v$database;

4. rman > backup incremental from scn scn_number database format ‘/tmp/forSTANDBY_%U’ tag FORSTANDBY;

At standby :

Do recovery at standby as :

5. Rman nocatalog target /

6. RMAN> catalog backuppiece ‘/tmp/forSTANDBY_%U’;

7. RMAN> recover database noredo;

8. RMAN> delete backup tag ‘FORSTANDBY’;

9. Alter database managed standby database using current logfile disconnect from session;

10. Select process,status from v$managed_standby;

11. Select sequence#,applied from v$archived_log;

12. Select max(sequence#) from v$log and match if it is same as of primary;





2. Copy controlfile from primary to standby :

At primary :

1. RMAN>backup current controlfile for standby;

or

2. RMAN> backup current controlfile for standby format ‘/tmp/controflile.ctl’;

At standby :

3. RMAN>restore standby controlfile from ‘/tmp/controlfile.ctl’;

4. Sql> shutdown immediate

5. SQL> startup nomount

6. SQL> alter database mount standby database;

7. SQL> recover managed standby database disconnect from session;

8. Check everything running fine : if yes then perfect otherwise :

9. SQL>select name from v$datafile ; (check all datafiles )

10. RMAN> set newname for datafile “datafile_name” to “standby_location”; or

11. RMAN> catalog start with '+diskgroup//datafile/';

12. SQL> alter database add standby logfile group 4 ‘+standby_location’ size 50M; (add same no of standby logfiles as of online redo log files).

13. SQL>shutdown immediate

14. SQL>startup nomount

15. SQL>alter database mount standby database;

16. RMAN>recover database ; (check incarnation and scn should be same as of primary)

17. SQL>recover managed standby database using current logfile disconnect from session;

18. Check mrp is running or not.

19. Check log sequence# on both databases.



3. Register logfiles:

1. Locate the missing log file using SQL>SELECT SEQUENCE#, APPLIED FROM V$ARCHIVED_LOG;

2. Copy all the missing log files from primary archive destination to standby archive destination;

3. SQL>Alter database register logfile ‘log_file_path’;

4. Now check status of mrp process.