Verify the fast-start failover configuration

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Scenarios Using the DGMGRL Command-Line Interface

Step 8 Verify the fast-start failover configuration

Use the SHOW CONFIGURATION command to display the readiness of the fast-start failover configuration:

DGMGRL> SHOW CONFIGURATION VERBOSE;

Configuration

Name: DRSolution Enabled: YES

Protection Mode: MaxAvailability Fast-Start Failover: ENABLED

Databases:

North_Sales - Primary database

DR_Sales - Physical standby database

In the example, note that the FastStartFailoverThreshold value is 30 seconds. This is the default value.

7.7 Scenario 6: Performing Routine Management Tasks

There may be situations in which you want to change the state or properties of the databases in a broker configuration to perform routine maintenance on one or more databases. You might also need to temporarily disable broker management of databases in a configuration.

7.7.1 Changing Properties and States

As you monitor the configuration, you might need to dynamically modify the states of the databases or their properties. The following sections show how to change the state or properties of the databases in the configuration.

7.7.1.1 Alter a Database Property

You can modify the values of database properties at any time—if the database is enabled, disabled, online, or offline.

Example 7–3 shows how to use the EDIT DATABASE command to change the LogArchiveTrace property to the value 127 for the North_Sales database.

Example 7–3 Altering a Database Property

DGMGRL> EDIT DATABASE 'North_Sales' SET PROPERTY 'LogArchiveTrace'='127';

DGMGRL returns the following message to indicate that the LogArchiveTrace property was updated successfully in the Data Guard configuration file:

Property "LogArchiveTrace" updated

If the configuration is currently disabled, the database does not use the new property value until you enable the broker configuration with the ENABLE CONFIGURATION command.

Scenario 6: Performing Routine Management Tasks

7.7.1.2 Alter the State of a Standby Database

You might want to use your physical standby database temporarily for reporting applications. To change the state of the standby database to read-only, enter the EDIT DATABASE command as shown in Example 7–4.

Example 7–4 Altering a Standby Database State

DGMGRL> EDIT DATABASE 'DR_Sales' SET STATE='READ-ONLY';

Succeeded.

Log files are still being received when you put the physical standby database in the read-only state. The broker stops Redo Apply from applying the redo data to the standby database.

7.7.1.3 Alter the State of a Primary Database

You might want to stop the transmittal of log files to the standby database. To change the state of the primary database to accommodate this, use the EDIT DATABASE North_Sales SET STATE=LOG-TRANSPORT-OFF command. You can also set the primary database OFFLINE, which effectively shuts down the primary database and disables the broker from managing the configuration (shown in Example 7–5).

Example 7–5 Altering a Primary Database State

DGMGRL> EDIT DATABASE 'North_Sales' SET STATE='OFFLINE';

DGMGRL returns the following message to indicate the command was successfully executed:

Operation requires shutdown of instance "sales1" on database "North_Sales"

Shutting down instance "sales1"...

Database closed.

Database dismounted.

ORACLE instance shut down.

To change the primary state back to ONLINE, you must start the primary database.

7.7.2 Disabling the Configuration and Databases

When you disable the broker configuration or any of its databases, you are disabling the broker’s management of those objects and are effectively removing your ability to use DGMGRL to manage and monitor the disabled object. However, disabling the broker’s management of a broker configuration does not affect the actual operation of the underlying Data Guard configuration or the databases. For example, the redo transport services and log apply services in the Data Guard configuration continue to function unchanged, but you can no longer manage them with DGMGRL.

7.7.2.1 Disable a Configuration

You must use the DISABLE CONFIGURATION command to disable management of the entire broker configuration including the primary database as shown in

Example 7–6.

Example 7–6 Disabling the Configuration and Primary Database DGMGRL> DISABLE CONFIGURATION;

Scenario 6: Performing Routine Management Tasks

The only way to disable broker management of the primary database is to use the DISABLE CONFIGURATION command; the DISABLE DATABASE command only disables management of a standby database.

Disabling the broker’s management of an object does not remove or delete its profile from the broker configuration file. You can reenable your ability to use DGMGRL (or Enterprise Manager) to manage the object by entering the appropriate ENABLE CONFIGURATION or ENABLE DATABASE command.

7.7.2.2 Disable a Standby Database

You use the DISABLE DATABASE command when you temporarily do not want the broker to manage and monitor a standby database.

You can explicitly disable broker management of a standby database to prevent it from being brought online when the rest of the configuration is brought online. Example 7–7 shows how to disable the DR_Sales standby database.

Example 7–7 Disabling a Standby Database DGMGRL> DISABLE DATABASE 'DR_Sales';

Disabled.

When running in either the maximum protection or maximum availability mode, the broker prevents you from disabling the last standby database that supports the protection mode.

7.7.3 Removing the Configuration or a Standby Database

When you use either the REMOVE CONFIGURATION or REMOVE DATABASE

command, you effectively delete the configuration or standby database profile from the broker configuration file, removing the ability of the Data Guard broker to manage the configuration or the standby database, respectively.

A remove operation does not remove or delete the actual Data Guard configuration underneath, nor does it affect the operation of the actual Data Guard configuration and its databases.

Note: If you disable management of a configuration while connected to the standby database, you must connect to the primary database to reenable the configuration.

Note: If you disable management of a standby database while connected to that standby database, you must connect to the primary database or another enabled standby database to reenable broker-management of the standby database.

Caution: If you disable broker management of a standby database in the broker configuration, that standby database cannot be used by the broker as a failover target in the event of loss of the primary database.

Scenario 6: Performing Routine Management Tasks

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