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Oracle® Data Guard Concepts and Administration
10g Release 1 (10.1)

Part Number B10823-01
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F
Sample Disaster Recovery ReadMe File

In a multiple standby database configuration, you cannot assume that the database administrator (DBA) who set up the multiple standby database configuration is available to decide which standby database to fail over to in the event of a disaster. Therefore, it is imperative to have a disaster recovery plan at each standby site, as well as at the primary site. Each member of the disaster recovery team needs to know about the disaster recovery plan and be aware of the procedures to follow.

Example F-1 shows the kind of information that the person who is making the decision would need when deciding which standby database should be the target of the failover.

A ReadMe file is created and maintained by the DBA and should describe how to:

Example F-1 Sample Disaster Recovery ReadMe File

----------------Standby Database Disaster Recovery ReadMe File----------------

Warning:
********************************************************************************
Perform the steps in this procedure only if you are responsible for failing over 
to a standby database after the primary database fails.

If you perform the steps outlined in this file unnecessarily, you might corrupt 
the entire database system.
********************************************************************************

Multiple Standby Database Configuration:

No.     Location       Type     IP Address
--- --------------- --------- --------------
 1   San Francisco   Primary   128.1.124.25 
 2   San Francisco   Standby   128.1.124.157
 3   Boston          Standby   136.132.1.55
 4   Los Angeles     Standby   145.23.82.16
 5   San Francisco   Standby   128.1.135.24

You are in system No. 3, which is located in Boston.

Perform the following steps to fail over to the most up-to-date and available 
standby database:

1. Log on to the local standby database as a DBA.

    a)  Log on with the following user name and password:

               username: Standby3
               password: zkc722Khn

    b)  Invoke SQL*Plus as follows:

        % sqlplus
     
    c)  Connect as the DBA as follows:

        CONNECT sys/s23LsdIc AS SYSDBA

2.  Connect to as many remote systems as possible. You can connect to a maximum
    of four systems. System 4 does not have a firewall, so you can connect to it
    directly. Systems 1, 2, and 5 share the same firewall host.  You need to go
    to the firewall host first and then connect to each system.  The IP address
    for the firewall host is 128.1.1.100.  Use the following user name and
    password:
               username: Disaster
               password: 82lhsIW32

3.  Log on to as many remote systems as possible with the following user names
    and passwords:

    Login information:

    No.     Location     IP Address    username   password
    --- --------------- ------------- ---------- ----------
    1   San Francisco   128.1.124.25   Oracle9i   sdd290Ec
    2   San Francisco   128.1.124.157  Standby2   ei23nJHb
    3                    (L o c a l)
    4   Los Angeles     145.23.82.16   Standby4   23HHoe2a
    5   San Francisco   128.1.135.24   Standby5   snc#$dnc

4.  Invoke SQL*Plus on each remote system you are able to log on to as follows:

    % sqlplus

5.  Connect to each remote database as follows:

    CONNECT sys/password AS SYSDBA

    The DBA passwords for each location are:

    No.     Location      Password
    --- --------------- -----------
    1   San Francisco     x2dwlsd91
    2   San Francisco     a239s1DAq
    3           (L o c a l)
    4   Los Angeles       owKL(@as23
    5   San Francisco     sad_KS13x

6.  If you are able to log on to System 1, invoke SQL*Plus and execute the
    following statements:

    SQL> SHUTDOWN IMMEDIATE;
    SQL> STARTUP PFILE=PRMYinit.ora;

    Note: If you are able to execute the STARTUP statement successfully, the
          primary database has not been damaged.  Do not continue with this
          procedure.

7.  Execute the following SQL statements on each standby database (including the
    one on this system) that you were able to connect to:

    SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;
    SQL> SELECT THREAD#, MAX(SEQUENCE#) FROM V$LOG_HISTORY GROUP BY THREAD#;

    Compare the query results of each standby database. Fail over to the
    standby database with the largest sequence number.

8.  Fail over to the standby database with the largest sequence number.

    On the standby database with the largest sequence number, invoke SQL*Plus
    and execute the following SQL statements:

    SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE 
      2> DISCONNECT FROM SESSION;
    SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE FINISH;
    SQL> ALTER DATABASE COMMIT TO SWITCHOVER TO PRIMARY;
    SQL> SHUTDOWN IMMEDIATE;
    SQL> STARTUP PFILE=Failover.ora;

9.  Update the other standby databases with the new primary database information 
and ensure the log transport and log apply services are working correctly.

------------End of Standby Database Disaster Recovery ReadMe File-------------