Time for action – enabling Active Data Guard if the standby database is shut down

1. If the standby database is completely shut down, use the following steps to enable Active Data Guard. Now start the database normally as follows:

   [oracle@oracle-stby ~]$ sqlplus / as sysdba
   SQL*Plus: Release 11.2.0.1.0 Production on Tue Nov 6 12:13:27 2012
   Copyright (c) 1982, 2009, Oracle.  All rights reserved.
   Connected to an idle instance.
   SQL> startup
   ORACLE instance started.
   Total System Global Area  818401280 bytes
   Fixed Size                  2217792 bytes
   Variable Size             528484544 bytes
   Database Buffers          285212672 bytes
   Redo Buffers                2486272 bytes
   Database mounted.
   Database opened.
   SQL>

2. Once the database is opened successfully, by default it will be in the Read Only mode because it's a standby control file. Now start Redo Apply as follows:

   SQL> select db_unique_name,open_mode from v$database;
   DB_UNIQUE_NAME  OPEN_MODE
   --------------- --------------------
   INDIA_UN...