Mir Sayeed Hassan – Oracle Blog

Failover by using the DGMGRL

On Primary Database

[oracle@pr ~]$ !sq
sqlplus / as sysdba

SQL>  SELECT NAME,DB_UNIQUE_NAME, OPEN_MODE,DATABASE_ROLE FROM V$DATABASE;
NAME      DB_UNIQUE_NAME                 OPEN_MODE            DATABASE_ROLE
-------- ------------------------------ -------------------- ----------------
PR        pr                             READ WRITE           PRIMARY

On Standby Database

[oracle@std scripts]$ !sq
sqlplus / as sysdba

SQL> SELECT NAME,DB_UNIQUE_NAME, OPEN_MODE,DATABASE_ROLE FROM V$DATABASE;
NAME      DB_UNIQUE_NAME                 OPEN_MODE            DATABASE_ROLE
--------- ------------------------------ -------------------- ----------------
PR        std                            MOUNTED              PHYSICAL STANDBY

SQL> exit

Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

[oracle@std scripts]$ dgmgrl

DGMGRL for Linux: Version 11.2.0.4.0 - 64bit Production
Copyright (c) 2000, 2009, Oracle. All rights reserved.
Welcome to DGMGRL, type "help" for information.

DGMGRL> conn sys/sys
Unrecognized command "conn", try "help"

DGMGRL> connect sys/sys
Connected.

DGMGRL> show configuration

Configuration - PRDG
Protection Mode: MaxPerformance
Databases:
pr  - Primary database
std - Physical standby database
Fast-Start Failover: DISABLED
Configuration Status:
SUCCESS

DGMGRL> show database 'PR';
Object "PR" was not found

DGMGRL> show database 'pr';

Database - pr
Role:            PRIMARY
Intended State:  TRANSPORT-ON
Instance(s):
pr
Database Status:
SUCCESS

Shutdown abort on primay database

SQL> shu abort

ORACLE instance shut down.
On standby database

DGMGRL> failover to 'std'

Performing failover NOW, please wait...
Failover succeeded, new primary is "std"
Check the standby database status

SQL> select status from v$instance;

STATUS
------------
OPEN

SQL> SELECT NAME,DB_UNIQUE_NAME, OPEN_MODE,DATABASE_ROLE FROM V$DATABASE;

NAME      DB_UNIQUE_NAME                 OPEN_MODE            DATABASE_ROLE
--------- ------------------------------ -------------------- ----------------
PR        std                            READ WRITE           PRIMARY

[oracle@std scripts]$ dgmgrl

DGMGRL for Linux: Version 11.2.0.4.0 - 64bit Production
Copyright (c) 2000, 2009, Oracle. All rights reserved.
Welcome to DGMGRL, type "help" for information.

DGMGRL> connect sys/sys
Connected.

DGMGRL> SHOW CONFIGURATION

Configuration - PRDG
Protection Mode: MaxPerformance
Databases:
std - Primary database
pr  - Physical standby database (disabled)
ORA-16661: the standby database needs to be reinstated
Fast-Start Failover: DISABLED
Configuration Status:
SUCCESS

DGMGRL> show database 'pr'

Database - pr
Role:            PHYSICAL STANDBY
Intended State:  APPLY-ON
Transport Lag:   (unknown)
Apply Lag:       (unknown)
Apply Rate:      (unknown)
Real Time Query: OFF
Instance(s):
pr
Database Status:
ORA-16661: the standby database needs to be reinstated

SQL> SELECT NAME,DB_UNIQUE_NAME, OPEN_MODE,DATABASE_ROLE FROM V$DATABASE;

NAME      DB_UNIQUE_NAME                 OPEN_MODE            DATABASE_ROLE
--------- ----------------------------- -------------------- ----------------
PR        std                            READ WRITE           PRIMARY

========================Hence Tested & Verified in our test env===================