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Standby Database

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Primary Database Setup

STBY=
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = myServerName)(PORT = 1512))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = STBY.world)
    )
  )
log_archive_start = true
log_archive_dest_1 = "location=c:\Oracle\oradata\SID\archive\ mandatory reopen=5"
log_archive_dest_state_1 = enable
log_archive_format = %%ORACLE_SID%%T%TS%S.ARC

log_archive_dest_2 = "service=STBY optional reopen=5"
log_archive_dest_state_2 = enable

Standby Database Setup

#use the standby service name
service_names = STBY.world

#reference the standby controlfile
control_files = ("c:\Oracle\oradata\SID\stbycf.f")

#switch archiving and reference archive directory
log_archive_start = false
log_archive_dest = c:\Oracle\oradata\SID\archive\
standby_archive_dest = c:\Oracle\oradata\SID\archive\
log_archive_format = %%ORACLE_SID%%T%TS%S.ARC
(ADDRESS_LIST =
  (ADDRESS = (PROTOCOL = TCP)(HOST = ntfm451)(PORT = 1512))
)

STANDBY_LISTENER = (ADDRESS_LIST=
 (ADDRESS=(PROTOCOL=tcp)(PORT=1512)(HOST=myHost))
)

The file should resemble the following.

# LISTENER.ORA Network Configuration File: C:\Oracle\Ora817\network\admin\listener.ora
# Generated by Oracle configuration tools.

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
      )
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = TCP)(HOST = myHost)(PORT = 1521))
      )
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = TCP)(HOST = myHost)(PORT = 1512))
      )
    )
    (DESCRIPTION =
      (PROTOCOL_STACK =
        (PRESENTATION = GIOP)
        (SESSION = RAW)
      )
      (ADDRESS = (PROTOCOL = TCP)(HOST = myHost)(PORT = 2481))
    )
  )

STANDBY_LISTENER = (ADDRESS_LIST=
 (ADDRESS=(PROTOCOL=tcp)(PORT=1512)(HOST=myHost))
)



SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PLSExtProc)
      (ORACLE_HOME = C:\Oracle\Ora817)
      (PROGRAM = extproc)
    )
    (SID_DESC =
      (ORACLE_HOME = C:\Oracle\Ora817)
      (SID_NAME = PGOAL1)
    )
  )
STBY=
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = myServerName)(PORT = 1512))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = STBY.world)
    )
  )

At this point the recovery process can start.

Standby Recovery

Regular recovery requires archive logs to be copied manually between the server and user initiation of the recovery process.

SQL> CONNECT sys/password AS SYSDBA
SQL> STARTUP NOMOUNT PFILE=C:\Oracle\Admin\SID\PFile\init.ora
SQL> ALTER DATABASE MOUNT STANDBY DATABASE;
SQL> RECOVER STANDBY DATABASE;

This process must be repeated every time archive logs are manually transfered.

Managed Standby Recovery

During managed recovery the transfer of archivelogs is controlled by the servers without user intervention.

SQL> CONNECT sys/password AS SYSDBA
SQL> STARTUP NOMOUNT PFILE=C:\Oracle\Admin\SID\PFile\init.ora
SQL> ALTER DATABASE MOUNT STANDBY DATABASE;
SQL> RECOVER MANAGED STANDBY DATABASE;

This window will then hang indefinitely while it continues to look for archive logs to apply. To stop the recovery open another sqlplus session and type:

SQL> RECOVER MANAGED STANDBY DATABASE CANCEL;

Read Only Database

The standby database can be opened in read only mode at any point. While open in this mode new archive logs are not applied to the database.

SQL> -- Cancel recovery if necessary
SQL> RECOVER MANAGED STANDBY DATABASE CANCEL;
SQL> ALTER DATABASE OPEN READ ONLY;

The database can subsequently be switched back to recovery mode as follows:

SQL> CONNECT sys/password AS SYSDBA
SQL> SHUTDOWN IMMEDIATE
SQL> STARTUP NOMOUNT PFILE=C:\Oracle\Admin\SID\PFile\init.ora
SQL> ALTER DATABASE MOUNT STANDBY DATABASE;
SQL> RECOVER MANAGED STANDBY DATABASE;

Backup Standby Database

Backups of the standby database can only be performed if the database is shut down or in read only mode. Read only mode is best for managed recovery systems as archive logs will still be transfered during the backup process, thus preventing gap sequences. Once the server is in the desired mode simple copy the appropriate database files.

For more information see:

Hope this helps. Regards Tim...

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