Configurable Properties

Configurable properties control the behavior of broker configuration members.

You can view and dynamically update the values of these properties using either DGMGRL or Cloud Control. However, some properties can only be updated through DGMGRL.

These properties control certain database initialization parameters and SQL statements that the broker uses to manage an Oracle Data Guard broker configuration. Therefore, you should not manually set those initialization parameters or issue those SQL statements on a broker configuration.

In most cases, the configurable property is said to apply to the entire member, meaning the value you set for the property applies to each instance of the member (that is, database or far sync instance). However, in a few cases, the configurable property is said to have instance-specific scope which means that for a multiple-instance database or far sync instance, it is possible that the values of some particular properties may differ between instances. The following table lists each configurable property and indicates whether the scope of the property is member-wide or instance-specific. If the Scope column contains:

• Member—The value of the property is database or far sync instance-wide, not instance or configuration specific.

• Instance—The value of the property is instance specific.

  If there is an asterisk (*) present, it indicates that the property value can be set for all instances of an Oracle RAC database using the EDIT INSTANCE * ON DATABASE command.

• Configuration—The value of the property is configuration wide, not instance or member specific.

Table 12-1 Configurable Properties

Configurable Property Name	Scope	Pertains To
AlternateLocation	Member	Redo transport services
ApplyInstances	Member	Redo Apply
ApplyInstanceTimeout	Member	Redo Apply and SQL Apply
ArchiveLocation	Member	Redo transport services
ApplyParallel	Member	Redo Apply
Binding	Member	Redo transport services
DelayMins	Member	Redo Apply and SQL Apply
DGConnectIdentifier	Member	Broker communication, Redo transport services
Encryption	Member	Redo transport services
FastStartFailoverTarget	Member	Fast-start failover
LogShipping	Member	Redo transport services
LogXptMode	Member	Redo transport services
MaxFailure	Member	Redo transport services
NetTimeout	Member	Redo transport services
ObserverConnectIdentifier	Member	Fast-start failover
PreferredApplyInstance	Member	Redo Apply and SQL Apply
PreferredObserverHosts	Member	Fast-start failover
RedoCompression	Member	Redo transport services
RedoRoutes	Member	Redo transport services
ReopenSecs	Member	Redo transport services
StandbyAlternateLocation	Member	Redo transport services
StandbyArchiveLocation	Member	Redo transport services
StaticConnectIdentifier	Instance	Instance Startup and Shutdown
TransportDisconnectedThreshold	Member	Redo transport services
TransportLagThreshold	Member	Redo transport services

Note:

Starting with Oracle Database Release 19c, configurable properties that map directly to database initialization parameters and logical standby attributes are not maintained within the broker configuration file. See the "Deprecated Features" section in Changes in Oracle Database Release 21c for Oracle Data Guard Broker for a list of deprecated initialization parameters and logical standby attributes.

Note:

When a broker configuration with its primary database is created and members are added to the configuration, the broker imports existing settings from the members to set many of the properties. If importing an existing setting fails, or if a property value is not imported, then the broker uses a broker default value. The default values and whether or not a property is imported is indicated within each property description.

See Also:

Managing the Members of a Broker Configuration for more information about property management

Broker Controlled Database Initialization Parameters and SQL Statements

The following database initialization parameters are controlled by broker configurable properties. Therefore, you should not set these parameters manually:

• LOG_ARCHIVE_DEST_n

• LOG_ARCHIVE_DEST_STATE_n

Note:

If the SERVICE clause is not included, it is not subject to broker control and can be changed.

The broker also uses configurable property settings to manage how apply is to be started. Therefore, the following SQL statements are managed automatically by the broker:

• ALTER DATABASE RECOVER MANAGED STANDBY DATABASE

• ALTER DATABASE START LOGICAL STANDBY APPLY IMMEDIATE

• AlternateLocation
  The AlternateLocation configurable property specifies an alternate online redo log archive location for primary, logical, and snapshot standby databases when the location specified by the ArchiveLocation configurable property fails.
• ArchiveLocation
  The ArchiveLocation configurable property specifies the online redo log archive location for primary, logical, and snapshot standby databases.
• ApplyInstances
  The ApplyInstances property lets you specify how many physical standby instances run Redo Apply.
• ApplyInstanceTimeout
  The ApplyInstanceTimeout configurable property specifies the number of seconds the broker waits after detecting the current apply instance failed before initiating the apply instance failover.
• ApplyLagThreshold
  The ApplyLagThreshold configurable property generates a warning status for a logical or physical standby when the member's apply lag exceeds the value specified by the property.
• ApplyParallel
  The ApplyParallel configurable property specifies whether Redo Apply should use multiple processes to apply redo data to the physical standby database.
• Binding
  The Binding configurable property specifies whether the destination is MANDATORY or OPTIONAL.
• DelayMins
  The DelayMins configurable property specifies the number of minutes log apply services will delay applying the archived redo log data on the standby database.
• DGConnectIdentifier
  The DGConnectIdentifier configurable property specifies the connect identifier the broker uses when making connections to a configuration member.
• Encryption
  The Encryption configurable property is used to specify whether redo data is encrypted before transmitting it to a Recovery Appliance.
• FastStartFailoverTarget
  The FastStartFailoverTarget configuration property specifies the DB_UNIQUE_NAME of one or more standby databases that can act as target databases in a fast-start failover situation when the database on which the property is set is the primary database.
• LogShipping
  The broker uses the value of the LogShipping property when the primary database is in the TRANSPORT-ON state or when the physical standby or far sync instance forwards redo data to another member.
• LogXptMode
  The LogXptMode configurable property enables you to set the redo transport service.
• MaxFailure
  The MaxFailure configurable property specifies the maximum number of contiguous archiving failures before the redo transport services stop trying to transport archived redo log files to the standby database.
• NetTimeout
  The NetTimeout configurable property specifies the number of seconds the LGWR waits for Oracle Net Services to respond to a LGWR request.
• ObserverConnectIdentifier
  The ObserverConnectIdentifier configurable property specifies a connect identifier that can be used by the observer to connect to this database.
• PreferredApplyInstance
  The PreferredApplyInstance configurable property indicates that a particular instance is the preferred choice for serving log apply services.
• PreferredObserverHosts
  The PreferredObserverHosts configurable property allows you to list the hosts that you would prefer as hosts for the master observer when that database is in the primary role.
• RedoCompression
  The RedoCompression configurable property is used to specify whether redo data is transmitted to a standby database or far sync instance in compressed or uncompressed form.
• RedoRoutes
  The RedoRoutes property lets you override the default behavior by which a primary database sends the redo that it generates to every other redo transport destination in the configuration.
• ReopenSecs
  The ReopenSecs configurable property specifies the minimum number of seconds before the archiver process (ARCn, foreground, or log writer process) should try again to access a previously failed destination.
• StandbyAlternateLocation
  The StandbyAlternateLocation configurable property specifies an alternate standby redo log archive location to use when the location specified by the StandbyArchiveLocation configurable property fails.
• StandbyArchiveLocation
  The StandbyArchiveLocation configurable property specifies the standby redo log archive location. Oracle recommends that you always explicitly set the value.
• StaticConnectIdentifier
  The StaticConnectIdentifier configurable instance-specific property specifies the connection identifier that the DGMGRL client will use when starting database instances.
• TransportDisconnectedThreshold
  The TransportDisconnectedThreshold configurable property can be used to generate a warning status for a logical, physical, or snapshot standby, or a far sync instance when the last communication from the primary database exceeds the property value.
• TransportLagThreshold
  The TransportLagThreshold configurable property can be used to generate a warning status for a logical, physical, or snapshot standby, or a far sync instance when the member's transport lag exceeds the property value.