Now execute the following steps in order to use Data Guard broker commands for changing the Data Guard protection mode:
- We now have Maximum Performance as the default protection mode in our configuration. Let's check it through DGMGRL. We can connect the interface from the primary or standby as follows:
$ dgmgrl DGMGRL for Linux: Version 11.2.0.1.0 - 64bit Production Copyright (c) 2000, 2009, Oracle. All rights reserved. Welcome to DGMGRL, type "help" for information. DGMGRL> CONNECT / DGMGRL> SHOW CONFIGURATION; Configuration - PACKT Protection Mode: MaxPerformance Databases: TURKEY_UN - Primary database INDIA_UN - Physical standby database Fast-Start Failover: DISABLED Configuration Status: SUCCESS - Try to convert the configuration from Maximum Performance to the Maximum Availability mode as shown in the following command line:
DGMGRL> EDIT CONFIGURATION SET PROTECTION MODE AS MaxAvailability; Error: ORA-16627: operation disallowed since no standby databases would remain to support protection mode Failed.
Again, we should remember that we have to set the SYNC attribute of
log_archive_dest_nbefore converting the protection mode from Maximum Performance to Maximum Availability and Maximum Protection. - Check and then change the log transport service attribute via DGMGRL, as shown in the following statements:
DGMGRL> SHOW DATABASE VERBOSE 'TURKEY_UN' LogXptMode; LogXptMode = 'ASYNC' DGMGRL> SHOW DATABASE VERBOSE 'INDIA_UN' LogXptMode; LogXptMode = 'ASYNC'
- The log transport service attribute should be changed for both the primary and standby databases as shown in the following command line:
For primary:
DGMGRL> EDIT DATABASE 'TURKEY_UN' SET PROPERTY LOGXPTMODE='SYNC'; Property "logxptmode" updated DGMGRL> SHOW DATABASE VERBOSE 'TURKEY_UN' LogXptMode; LogXptMode = 'SYNC'
For standby:
DGMGRL> EDIT DATABASE 'INDIA_UN' SET PROPERTY LOGXPTMODE='SYNC'; Property "logxptmode" updated DGMGRL> SHOW DATABASE VERBOSE 'INDIA_UN' LogXptMode; LogXptMode = 'SYNC'
- Ensure that the standby redo logs exist and are created with the correct size on the standby database, as shown in the following query:
SQL> select group#,bytes from v$standby_log; GROUP# BYTES ---------- ---------- 4 52428800 5 52428800 6 52428800 7 52428800 - Now change the protection mode to Maximum Availability as shown in the following command line:
DGMGRL> EDIT CONFIGURATION SET PROTECTION MODE AS MaxAvailability; Succeeded.
- Check the configuration status as follows:
DGMGRL> SHOW CONFIGURATION; Configuration - PACKT Protection Mode: MaxAvailability Databases: TURKEY_UN - Primary database INDIA_UN - Physical standby database Fast-Start Failover: DISABLED Configuration Status: SUCCESS
The Protection status is changed to Maximum Availability. Ensure that the configuration status is SUCCESS.
We've successfully changed the protection mode from Maximum Performance to Maximum Availability using the DGMGRL command line interface.
Now change the Data Guard protection mode from Maximum Availability to Maximum Protection via DGMGRL. You should be able to make this change without restarting the primary database. Then try mode transition from Maximum Performance to Maximum Protection where you'll be prompted with the following warning:
ORA-16570: database needs restart
It's time to see how the protection mode can be changed with some clicks. Enterprise Manager Cloud Control offers great for monitoring and managing Data Guard environments. Changing the protection mode is also quite easy with this interface.