Manual Physical Standby Failover – Activate Standby Database or DR sync with standby database and need to open database

One:

First Check database listener, it should be running:

[oracle@DRDG ~]$ lsnrctl status

Two:

Check database mode and role, It should be MOUNTED and PHYSICAL STANDBY:

SQL> select name,open_mode,database_role from v$database;

NAME OPEN_MODE DATABASE_ROLE

--------- -------------------- ----------------

ABC MOUNTED PHYSICAL STANDBY

Three:

Copy archive logs from primary database, those yet to apply on standby database before activate it.

SQL> recover standby database until cancel;

AUTO

Four:

Activate standby database as primary database:

[oracle@DRDG ~]$ sqlplus / as sysdba

SQL> alter database activate standby database;

Database altered.

Five:

Shutdown standby database and startup:

SQL> shut immediate;

ORA-01109: database not open

Database dismounted.

ORACLE instance shut down.

SQL> startup

ORACLE instance started.

Total System Global Area 755769344 bytes

Fixed Size 2217184 bytes

Variable Size 448793376 bytes

Database Buffers 301989888 bytes

Redo Buffers 2768896 bytes

Database mounted.

Database opened.

 Standby database successfully activated as Primary database. Failover successful.

Post activity check, ensure database mode and role, it should be READ WRITE and PRIMARY.

SQL> select name,open_mode,database_role from v$database;

NAME OPEN_MODE DATABASE_ROLE

--------- -------------------- ----------------

ABC READ WRITE PRIMARY

Note: Please take full database backup after failover.

Note: Once old primary database is available for use then you can reconfigure standby database.

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