Create Standby Using DUPLICATE

Copy Files
Create the necessary directories on the standby server.

    $ mkdir -p /u01/app/oracle/oradata/BRTADB
    $ mkdir -p /u01/app/oracle/fast_recovery_area/BRTADB
    $ mkdir -p /u01/app/oracle/admin/BRTADB/adump

Copy the files from the primary to the standby server.

    $ # Standby controlfile to all locations.
    $ scp oracle@ol5-112-dga1:/tmp/db11g_stby.ctl /u01/app/oracle/oradata/BRTADB/control01.ctl

    scp oracle@192.168.77.1:/tmp/brtadbstd02.ctl /u01/app/oracle/oradata/brtadb/control01.ctl

    $ cp /u01/app/oracle/oradata/DB11G/control01.ctl /u01/app/oracle/fast_recovery_area/DB11G/control02.ctl

     cp /u01/app/oracle/oradata/brtadb/control01.ctl /fra/fast_recovery_area/brtadb/control02.ctl

    $ # Parameter file.
    $ scp oracle@ol5-112-dga1:/tmp/initDB11G_stby.ora /tmp/initDB11G_stby.ora

    scp oracle@192.168.77.1:/tmp/initBRTADBSTD02.ora /tmp/initBRTADBSTD02.ora


    $ # Remote login password file.
    $ scp oracle@ol5-112-dga1:$ORACLE_HOME/dbs/orapwDB11G $ORACLE_HOME/dbs

    scp oracle@192.168.77.1:$ORACLE_HOME/dbs/ora* $ORACLE_HOME/dbs

Start Listener

When using active duplicate, the standby server requires static listener configuration in a "listener.ora" file. In this case I used the following configuration.

    SID_LIST_LISTENER =
      (SID_LIST =
        (SID_DESC =
          (GLOBAL_DBNAME = DB11G.WORLD)
          (ORACLE_HOME = /u01/app/oracle/product/11.2.0/db_1)
          (SID_NAME = DB11G)
        )
      )

    LISTENER =
      (DESCRIPTION_LIST =
        (DESCRIPTION =
          (ADDRESS = (PROTOCOL = TCP)(HOST = ol5-112-dga2.localdomain)(PORT = 1521))
        )
        (DESCRIPTION =
          (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
        )
      )

    ADR_BASE_LISTENER = /u01/app/oracle

Make sure the listener is started on the standby server.

    $ lsnrctl start

Create Standby Redo Logs on Primary Server

The DUPLICATE command automatically creates the standby redo logs on the standby. To make sure the primary database is configured for switchover, we must create the standby redo logs on the primary server.

    ALTER DATABASE ADD STANDBY LOGFILE ('/u01/app/oracle/oradata/DB11G/standby_redo01.log') SIZE 50M;
    ALTER DATABASE ADD STANDBY LOGFILE ('/u01/app/oracle/oradata/DB11G/standby_redo02.log') SIZE 50M;
    ALTER DATABASE ADD STANDBY LOGFILE ('/u01/app/oracle/oradata/DB11G/standby_redo03.log') SIZE 50M;
    ALTER DATABASE ADD STANDBY LOGFILE ('/u01/app/oracle/oradata/DB11G/standby_redo04.log') SIZE 50M;
Start the auxillary instance on the standby server by starting it using the temporary "init.ora" file.

    $ export ORACLE_SID=BRTADB
    $ sqlplus / as sysdba

    SQL> STARTUP NOMOUNT PFILE='/tmp/initBRTADBSTD02.ora';

Connect to RMAN, specifying a full connect string for both the TARGET and AUXILLARY instances. DO not attempt to use OS authentication.

    $ rman TARGET sys/password@BRTADB AUXILIARY sys/password@BRTADBSTD02

Now issue the following DUPLICATE command.

    DUPLICATE TARGET DATABASE
      FOR STANDBY
      FROM ACTIVE DATABASE
      DORECOVER
      SPFILE
        SET db_unique_name='BRTADBSTD02' COMMENT 'Is standby'
        SET LOG_ARCHIVE_DEST_3='SERVICE=BRTADB ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=BRTADB'
        SET FAL_SERVER='BRTADB' COMMENT 'Is primary'
      NOFILENAMECHECK;

A brief explanation of the individual clauses is shown below.

    FOR STANDBY: This tells the DUPLICATE command is to be used for a standby, so it will not force a DBID change.

    FROM ACTIVE DATABASE: The DUPLICATE will be created directly from the source datafile, without an additional backup step.

    DORECOVER: The DUPLICATE will include the recovery step, bringing the standby up to the current point in time.

    SPFILE: Allows us to reset values in the spfile when it is copied from the source server.

    NOFILENAMECHECK: Destination file locations are not checked.

Once the command is complete, we can start the apply process.


Start Apply Process


Start the apply process on standby server.


    ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION;

If you need to cancel the apply process, issue the following command.

    ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;

If you prefer, you can set a delay between the arrival of the archived redo log and it being applied on the standby server using the following commands.

    ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;
    ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DELAY 30 DISCONNECT FROM SESSION;

    ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;
    ALTER DATABASE RECOVER MANAGED STANDBY DATABASE NODELAY DISCONNECT FROM SESSION;

Test Log Transport

On the primary server, check the latest archived redo log and force a log switch.

    ALTER SESSION SET nls_date_format='DD-MON-YYYY HH24:MI:SS';

    SELECT sequence#, first_time, next_time
    FROM   v$archived_log
    ORDER BY sequence#;

    ALTER SYSTEM SWITCH LOGFILE;

Check the new archived redo log has arrived at the standby server and been applied.

    ALTER SESSION SET nls_date_format='DD-MON-YYYY HH24:MI:SS';

    SELECT sequence#, first_time, next_time, applied
    FROM   v$archived_log
    ORDER BY sequence#;

Protection Mode

There are three protection modes for the primary database:

    Maximum Availability: Transactions on the primary do not commit until redo information has been written to the online redo log and the standby redo logs of at least one standby location. If no standby location is available, it acts in the same manner as maximum performance mode until a standby becomes available again.
  
 Maximum Performance: Transactions on the primary commit as soon as redo information has been written to the online redo log. Transfer of redo information to the standby server is asynchronous, so it does not impact on performance of the primary.
   
Maximum Protection: Transactions on the primary do not commit until redo information has been written to the online redo log and the standby redo logs of at least one standby location. If not suitable standby location is available, the primary database shuts down.

By default, for a newly created standby database, the primary database is in maximum performance mode.

    SELECT protection_mode FROM v$database;

    PROTECTION_MODE
    --------------------
    MAXIMUM PERFORMANCE

    SQL>

The mode can be switched using the following commands. Note the alterations in the redo transport attributes.

    -- Maximum Availability.
    ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='SERVICE=db11g_stby AFFIRM SYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=DB11G_STBY';
    ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE AVAILABILITY;

    -- Maximum Performance.
    ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='SERVICE=db11g_stby NOAFFIRM ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=DB11G_STBY';
    ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE;

    -- Maximum Protection.
    ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='SERVICE=db11g_stby AFFIRM SYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=DB11G_STBY';
    SHUTDOWN IMMEDIATE;
    STARTUP MOUNT;
    ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PROTECTION;
    ALTER DATABASE OPEN;