Switchover from primary to standby

1. Check switchover status before switching database.

SQL>select switchover_status from v$database;

You must see “TO_STANDBY” as result.
Otherwise

2. SQL>alter system switch logfile;

3. Switch primary database to standby database.

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

 SQL>shutdown immediate;

 SQL>startup nomount;

4.SQL>alter database mount standby database;

Defer for archive log apply. Because I didn’t set my standby database as primary yet.

5. SQL>alter system set log_archive_dest_state_2=defer;

Switch standby database to primary. Check switchover status before switching database