Reinstate Failed Primary Database using Flashback:-

Reinstate Failed Primary Database using Flashback:-

 

Methods to Reinstate database using Flashback:-

 

1) Using DGMGRL

2) Using SQL*PLUS

 

1) Using DGMGRL:-

 

1. Startup the Failed Primary Database in the Mount stage:

SQL> startup mount

 

2. Issue the following command while connected to any database in the broker configuration, except the database that is to be reinstated:

 

DGMGRL> REINSTATE DATABASE PROD_DGP;

 

If the REINSTATE DATABASE fails to start the Failed Primary Database, then manually start the database in mount stage and reissue the reinstate command.

 

2. Using SQL*PLUS:-

 

Step 1 Determine the Standby Became Primary SCN.

Step 2 Flashback the Failed Primary Database.

Step 3 Convert to physical standby database.

Step 4 Restart Redo Transport.

Step 5 Start Redo Apply.

 

Step 1) Determine the SCN at which the old standby database became the primary database:-

 

SQL> SELECT TO_CHAR(STANDBY_BECAME_PRIMARY_SCN) FROM V$DATABASE;

 

Step 2) Flashback the Failed Primary Database to SCN standby_became_primary_scn:-

 

SQL> SHUTDOWN IMMEDIATE;

SQL> startup mount

SQL> FLASHBACK DATABASE TO SCN <standby_became_primary_scn of step 1>;

 

Step 3) Convert the database to a physical standby database and Restart database in mount stage:-

 

SQL> ALTER DATABASE CONVERT TO PHYSICAL STANDBY;

SQL> SHUTDOWN IMMEDIATE;

SQL> STARTUP MOUNT;

 

Step 4 Restart Redo Transport to the New Physical Standby Database:-

 

1. If you have not set the remote archive destination on current primary then set remote archive destination:

 

SQL>ALTER SYSTEM SET LOG_ARCHIVE_DEST_2 = ‘SERVICE=<service_name_of_failed_primary_database> VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=<db_unique_name>’ SCOPE=BOTH;

 

2. Enable the destination

 

SQL>ALTER SYSTEM SET LOG_ARCHIVE_DEST_STATE_2=ENABLE;

 

3. Perform a log switch to ensure that standby database begins receiving redo data from the new primary database

 

SQL> ALTER SYSTEM SWITCH LOGFILE;

SQL> SELECT DEST_ID, STATUS, ERROR FROM V$ARCHIVE_DEST WHERE DEST_ID=2;

 

Step 5 Start Redo Apply.

SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION;