Switchover from primary.to standby

Primary Database ( TRAIN )

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

NAME      OPEN_MODE            DATABASE_ROLE
--------- -------------------- ----------------
TRAIN     READ WRITE           PRIMARY
<testing switchover status>
SQL> select switchover_status from v$database;

SWITCHOVER_STATUS
--------------------
FAILED DESTINATION

SQL> alter system switch logfile;

System altered.

SQL> /
System altered.
<testing switchover status>
SQL> select switchover_status from v$database;

SWITCHOVER_STATUS
--------------------
TO STANDBY

<switchover to standby>
SQL> alter database commit to switchover to standby;

Database altered.
<shutdown immediate>
SQL> shutdown immediate;
ORA-01507: database not mounted


ORACLE instance shut down.
<startup mount>
SQL> startup mount
ORACLE instance started.

Total System Global Area 1.1458E+10 bytes
Fixed Size                  2217120 bytes
Variable Size            9831451488 bytes
Database Buffers         1610612736 bytes
Redo Buffers               13496320 bytes
Database mounted.
SQL> select name,open_mode,database_role from v$database;

NAME      OPEN_MODE            DATABASE_ROLE
--------- -------------------- ----------------
TRAIN     MOUNTED              PHYSICAL STANDBY
<start managed recovery again>
SQL> alter database recover managed standby database disconnect from session;

Database altered.

======================================================================
On Standby Database ( TRAINSBY )
======================================================================

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

NAME      OPEN_MODE            DATABASE_ROLE
--------- -------------------- ----------------
TRAIN     MOUNTED              PHYSICAL STANDBY

<checking switch over status>
SQL> select switchover_status from v$database;

SWITCHOVER_STATUS
--------------------
TO PRIMARY
<switchover to primary>
SQL> alter database commit to switchover to primary;

Database altered.
<shutdown immediate>
SQL> shutdown immediate
ORA-01109: database not open


Database dismounted.
ORACLE instance shut down.
<startup new primary database>
SQL> startup
ORACLE instance started.

Total System Global Area 1.0689E+10 bytes
Fixed Size                  2216200 bytes
Variable Size            3959426808 bytes
Database Buffers         6710886400 bytes
Redo Buffers               16945152 bytes
Database mounted.
Database opened.
SQL> select name,open_mode,database_role from v$database;

NAME      OPEN_MODE            DATABASE_ROLE
--------- -------------------- ----------------
TRAIN     READ WRITE           PRIMARY

SQL> alter system switch logfile;

System altered.