Use the SHOW FAST_START FAILOVER command to display the fast-start failover settings:
DGMGRL> SHOW FAST_START FAILOVER;
Fast-Start Failover: ENABLED Threshold: 30 seconds Target: DR_Sales
Observer: observer.foo.com Lag Limit: 30 seconds (not in use) Shutdown Primary: TRUE
Auto-reinstate: TRUE
Configurable Failover Conditions Health Conditions:
Corrupted Controlfile YES Corrupted Dictionary YES Inaccessible Logfile NO Stuck Archiver NO
Scenario 6: Performing Routine Management Tasks
Datafile Offline YES
Oracle Error Conditions: (none)
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 or disabled.
Example 7–3 shows how to use the EDIT DATABASE command to change the LogArchiveTrace configurable database 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.
7.7.1.2 Alter the State of a Standby Database
You might want to temporarily stop Redo Apply on a physical standby. To change the state of the standby database to APPLY-OFF, 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='APPLY-OFF'; Succeeded.
Redo data is still being received when you put the physical standby database in the APPLY-OFF state.
7.7.1.3 Alter the State of a Primary Database
You might want to stop the transmittal of redo data to the standby database. To change the state of the primary database to accommodate this, use the following command:
Scenario 6: Performing Routine Management Tasks
DGMGRL> EDIT DATABASE North_Sales SET STATE=TRANSPORT-OFF;
Succeeded.
To change the state of the primary database back to TRANSPORT-ON, do the following:
DGMGRL> EDIT DATABASE North_Sales SET STATE=TRANSPORT-ON;
Succeeded.
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.
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 7–5.
Example 7–5 Disabling the Configuration and Primary Database
DGMGRL> DISABLE CONFIGURATION;
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 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 enabled when the rest of the configuration is enabled. Example 7–6 shows how to disable the DR_Sales standby database.
Example 7–6 Disabling a Standby Database
DGMGRL> DISABLE DATABASE 'DR_Sales'; Disabled.
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.
Scenario 6: Performing Routine Management Tasks
When operating under either maximum protection mode 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 with the PRESERVE DESTINATIONS clause 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.