Oracle Database Switchover steps

# connect to DC // Production
sqlplus sys/S_Passw0rd@mmoney as sysdba << EOF
select DATABASE_ROLE, switchover_status from v$database;
alter database commit to switchover to standby with session shutdown;
shutdown immediate


SQL> select DATABASE_ROLE, switchover_status from v$database;

DATABASE_ROLE    SWITCHOVER_STATUS
---------------- --------------------
PRIMARY          TO STANDBY

SQL> alter database commit to switchover to standby with session shutdown;

Database altered.

SQL>


oracle@cstsp-05:/d01/product/oracle/diag/rdbms/martstby/PROD/trace$ ls -ltrh alert*.log
-rw-r-----   1 oracle  oinstall    449K Apr 14 00:37 alert_PROD.log
oracle@cstsp-05:/d01/product/oracle/diag/rdbms/PROD/PROD/trace$ tail -f alert_PROD.log
Switchover: Primary controlfile converted to standby controlfile succesfully.
Switchover: Complete - Database shutdown required
USER (ospid: 9094): terminating the instance
Sat Apr 14 00:37:57 2018
Instance terminated by USER, pid = 9094
Completed: alter database commit to switchover to standby with session shutdown
Shutting down instance (abort)
License high water mark = 24
Sat Apr 14 00:37:57 2018
Instance shutdown complete




# CONNECT TO DR
sqlplus sys/S_Passw0rd@mmoneydr as sysdba << EOF
select switchover_status from v$database;
alter database commit to switchover to primary;
alter database open;
select DATABASE_ROLE, switchover_status from v$database;




SQL> select switchover_status from v$database;

SWITCHOVER_STATUS
--------------------
TO PRIMARY

SQL> alter database commit to switchover to primary;

Database altered.

SQL> alter database open;

Database altered.

SQL> select DATABASE_ROLE, switchover_status from v$database;

DATABASE_ROLE    SWITCHOVER_STATUS
---------------- --------------------
PRIMARY          FAILED DESTINATION

SQL> /

DATABASE_ROLE    SWITCHOVER_STATUS
---------------- --------------------
PRIMARY          TO STANDBY

SQL>

# CONNECT TO DC

sqlplus sys/S_Passw0rd@mmoney as sysdba << EOF

startup mount;

alter database open read only;

recover managed standby database using current logfile disconnect;

select DATABASE_ROLE, switchover_status from v$database;

select sequence#,process,status from v$managed_standby;

EOF

SQL> startup mount

ORACLE instance started.

Total System Global Area 5150605312 bytes

Fixed Size                  3711144 bytes

Variable Size            2013273944 bytes

Database Buffers         3120562176 bytes

Redo Buffers               13058048 bytes

Database mounted.

SQL> alter database open read only;

Database altered.

SQL>

SQL> recover managed standby database using current logfile disconnect;

Media recovery complete.

SQL> select DATABASE_ROLE, switchover_status from v$database;

DATABASE_ROLE    SWITCHOVER_STATUS

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

PHYSICAL STANDBY NOT ALLOWED

SQL> select sequence#,process,status from v$managed_standby;

 SEQUENCE# PROCESS   STATUS

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

         0 ARCH      CONNECTED

      5703 ARCH      CLOSING

         0 ARCH      CONNECTED

         0 ARCH      CONNECTED

         0 ARCH      CONNECTED

         0 ARCH      CONNECTED

         0 ARCH      CONNECTED

         0 ARCH      CONNECTED

         0 ARCH      CONNECTED

         0 ARCH      CONNECTED

         0 RFS       IDLE

 SEQUENCE# PROCESS   STATUS

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

      5704 RFS       IDLE

         0 RFS       IDLE

      5704 MRP0      APPLYING_LOG

14 rows selected.

SQL>

Note : In case of  RAC switchover just keep up primary up and shutdown rest instances.