We have configured DG Broker in the Previous article. In this article, we will see scenarios that we can handle with DGMGRL command prompt.

To see how to configure DG broker.

Configure DG broker

1. Change LogXptmode

We can set LogXptMode to SYNC or ASYNC as per protection mode.

Syntax :

DGMGRL> EDIT DATABASE TESTDB SET PROPERTY LogXptMode=SYNC;

2. Enable/disable APPLY at DR

DGMGRL> edit database testdb set state=apply-off;
Succeeded.

Set apply on:

DGMGRL> edit database testdb set state=apply-on;
Succeeded.

3. Enable/disable TRANSPORT

DGMGRL> edit database std_testdb set state=transport-off;
Succeeded.
DGMGRL> edit database std_testdb set state=transport-on;
Succeeded.

4. Switchover

We can perform switchover operation using just one command with DGMGRL.

DGMGRL> SWITCHOVER TO STD_TESTDB;
Performing switchover NOW, please wait...
Operation requires a connection to instance "testdb" on database "std_testdb"
Connecting to instance "testdb"...
Connected.
New primary database "std_testdb" is opening...
Operation requires startup of instance "testdb" on database "testdb"
Starting instance "testdb"...
ORACLE instance started.
Database mounted.
Database opened.
Switchover succeeded, new primary is "std_testdb"

5. Failover

Use fail over command :

[oracle@test1 ~]$ dgmgrl sys/oracle@testdb
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.
Connected.
DGMGRL> show configuration;

Configuration - drdb

  Protection Mode: MaxPerformance
  Databases:
    std_testdb - Primary database
    testdb     - Physical standby database

Fast-Start Failover: DISABLED

Configuration Status:
SUCCESS

DGMGRL> failover to testdb;
Performing failover NOW, please wait...
Failover succeeded, new primary is "testdb"
DGMGRL>

6.  Re-instate after the fail over

After failover operation your Primary Database becomes unusable. We can reinstate Primary Database so that will get Physical Standby Role then.

DGMGRL> show configuration;

Configuration - drdb

  Protection Mode: MaxPerformance
  Databases:
    testdb     - Primary database
    std_testdb - Physical standby database (disabled)
      ORA-16661: the standby database needs to be reinstated

Fast-Start Failover: DISABLED

Configuration Status:
SUCCESS

DGMGRL>

Step 2: open old primary in mount mode

SQL> startup mount
ORACLE instance started.

Total System Global Area  663908352 bytes
Fixed Size		    2256192 bytes
Variable Size		  578814656 bytes
Database Buffers	   79691776 bytes
Redo Buffers		    3145728 bytes
Database mounted.

Step  3: REINSTATE database with DGMGRL

DGMGRL> reinstate database std_testdb;
Reinstating database "std_testdb", please wait...
Operation requires shutdown of instance "testdb" on database "std_testdb"
Shutting down instance "testdb"...
ORA-01109: database not open

Database dismounted.
ORACLE instance shut down.
Operation requires startup of instance "testdb" on database "std_testdb"
Starting instance "testdb"...
ORACLE instance started.
Database mounted.
Continuing to reinstate database "std_testdb" ...
Reinstatement of database "std_testdb" succeeded
DGMGRL>

Check configuration :

DGMGRL> show configuration;

Configuration - drdb

  Protection Mode: MaxPerformance
  Databases:
    testdb     - Primary database
    std_testdb - Physical standby database

Fast-Start Failover: DISABLED

Configuration Status:
SUCCESS

DGMGRL>

Stay tuned for More articles on Oracle DataGuard

Thank you for giving your valuable time to read the above information.

If you want to be updated with all our articles send us the Invitation or Follow us:

Telegram Channel: https://t.me/helporacle

Skant Gupta’s LinkedIn: www.linkedin.com/in/skantali/

Joel Perez’s LinkedIn: Joel Perez’s Profile

LinkedIn Group: Oracle Cloud DBAAS

Facebook Page: OracleHelp

 

About The Author

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.