Manual Switchover in Databguard

Primary :
SQL>select switchover_status from v$database;
SQL>alter database commit to switchover to physical standby with session shutdown;
SQL>shutdown immediate
SQL>startup nomount
SQL>alter database mount standby database;
Standby :
SQL>select switchover_status from v$database;
SQL>alter database commit to switchover to primary;
SQL>shutdown immediate
SQL>startup
New standby:SQL>alter database recover managed standby database disconnect from session;