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e-docs > WebLogic Server > Administration Console Online Help > Messaging Bridge |
Administration Console Online Help |
The WebLogic Messaging Bridge allows you to configure a forwarding mechanism between any two messaging products—thereby, providing interoperability between separate implementations of WebLogic JMS, or between WebLogic JMS and another messaging product. You can use the Messaging Bridge to integrate your messaging applications between:
A messaging bridge consists of two destinations that are being bridged: a source destination that the bridge reads messages from and a target destination where the bridge sends the messages that it receives from the source destination. For WebLogic JMS and third-party JMS products, a messaging bridge communicates with source and target destinations using the resource adapters provided with WebLogic Server. For non-JMS messaging products, a custom connector adapter must be obtained from a third-party OEM vendor or by contacting BEA Professional Services in order to access non-JMS source or target destinations.
Source and target bridge destinations can be either queues or topics. You can also specify a quality of service (QOS), as well as message filters, transaction semantics, and connection retry policies. Once a messaging bridge is configured, it is easily managed from the Administration Console, including temporarily suspending bridge traffic whenever necessary, tuning the execute thread pool size to suit your implementation, and monitoring the status of all your configured bridges.
Messaging Bridge Configuration Tasks
Before you can deploy a messaging bridge, you need to configure its required components:
About the Bridge's Resource Adapters
A messaging bridge uses resource adapters to communicate with the configured source and target JMS destinations. You need to associate both the source and target JMS destinations with a supported resource adapter in order for the bridge to communicate with them. The JNDI name for the adapter is configured as part of the resource adapter's deployment descriptor.
Note: Although WebLogic JMS includes a "General Bridge Destination" framework for accessing non-JMS messaging products, WebLogic Server does not provide supported connector adapters for such products. Therefore, you must obtain a custom connector adapter from a third-party OEM vendor and consult their documentation for configuration instructions. You can also contact BEA Professional Services for information about obtaining a custom connector adapter.
The supported resource adapters are located in the WL_HOME\server\lib directory and are described in the following table.
Provides transaction semantics via the XAResource. Used when the required QOS is Exactly-once. This envelops a received message and sends it within a user transaction (XA/JTA). The following requirements are necessary in order to use this resource adapter: Note: Before deploying this resource adapter, refer to the Using the Messaging Bridge to Interoperate with Different WebLogic Server Versions and Domains for specific transactional configuration requirements and guidelines. |
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Provides no transaction semantics. Used when the required QOS is Atmost-once or Duplicate-okay. If the requested QOS is Atmost-once, the resource adapter uses the AUTO_ACKNOWLEDGE mode. If the requested QOS is Duplicate-okay, CLIENT_ACKNOWLEDGE is used. Note: For more information about the acknowledge modes used in non-transacted sessions, see "WebLogic JMS Fundamentals" in Programming WebLogic JMS. |
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Provides interoperability when either the source or target destination is WebLogic Server 5.1. This resource adapter provides no transaction semantics; therefore, it only supports a QOS of Atmost-once or Duplicate-okay. If the requested QOS is Atmost-once, the resource adapter uses the AUTO_ACKNOWLEDGE mode. If the requested QOS is Duplicate-okay, CLIENT_ACKNOWLEDGE is used. |
You will specify the appropriate resource adapter by its JNDI name when you configure each source and target bridge destination.
Deploying the Bridge's Resource Adapters
Before you configure the messaging bridge destinations, deploy the appropriate resource adapters in the WebLogic Server domain that is hosting the messaging bridge, as follows:
For more information on deploying resource adapters, see "WebLogic Server Deployment" in Packaging and Deploying WebLogic Server Applications.
Configuring Source and Target Bridge Destinations
Each messaging bridge consists of two destinations that are being bridged: a source destination that the bridge reads messages from and a target destination where the bridge sends the messages that it receives from the source destination. Depending on the messaging products that need to be bridged, there are two types of Messaging Bridge destinations:
Before starting the procedures in this section, refer to the Using the Messaging Bridge to Interoperate with Different WebLogic Server Versions and Domains or Using the Messaging Bridge to Access a Third-Party Messaging Provider sections for specific configuration requirements and guidelines.
Configuring JMS Bridge Destinations
A JMSBridgeDestination instance defines a unique name for a bridge's source and target destinations within a WebLogic domain, the name of the adapter used to communicate with the specified destination, property information to pass to the adapter (Connection URL, Connection Factory JNDI Name, etc.), and, optionally, a user name and password.
When you finish defining attributes for a source JMS bridge destination, repeat these steps to configure a target JMS bridge destination, or vice versa. You will designate the source and target JMS Bridge Destinations in Configuring a Messaging Bridge.
To configure a source or target JMS bridge destination, follow these steps.
Note: In order to use the Exactly-once QOS for transactions, the JMS connection factory has to be a XAConnection Factory. For more information about connection factory and QOS requirements, refer to the Attributes table in Messaging Bridge --> Configuration --> General.
For more information about JMS bridge destination attributes, see JMS Bridge Destination --> Configuration.
When you finish defining attributes for a source JMS bridge destination, repeat these steps to configure a target JMS bridge destination, or vice versa. Then follow the instructions for Configuring a Messaging Bridge.
Configuring General Bridge Destinations
A general BridgeDestination instance defines a unique name for the source and target general bridge destinations within the WebLogic domain, the name of the adapter used to communicate with the specified destination, a list of properties to pass to the adapter, and, optionally, a user name and password.
Note: Although WebLogic JMS includes a "General Bridge Destination" framework for accessing non-JMS messaging products, WebLogic Server does not provide supported connector adapters for such products. Therefore, you must obtain a custom connector adapter from a third-party OEM vendor and consult their documentation for configuration instructions. You can also contact BEA Professional Services for information about obtaining a custom connector adapter.
When you finish defining attributes for a source general bridge destination, repeat these steps to configure a target general bridge destination, or vice versa. You will designate the source and target general Bridge Destinations in Configuring a Messaging Bridge.
To configure a source or target general bridge destination, follow these steps.
Note: WebLogic Server does not provide adapters for non-JMS messaging products. Therefore, you must use a specialized adapter from a third-party OEM vendor, or contact BEA Professional Services to obtain a custom adapter.
Note: For non-JMS messaging products that use adapters provided by a third-party OEM vendor, you should consult the vendor's documentation for property configuration instructions.
For more information about the general bridge destination attributes, see General Bridge Destination --> Configuration.
When you finish defining attributes for a source general bridge destination, repeat these steps to configure a target general bridge destination, or vice versa. Then follow the instructions for Configuring a Messaging Bridge.
Configuring a Messaging Bridge
A messaging bridge communicates with the configured source and target destinations. For each mapping of a source destination to a target destination, whether it is another WebLogic JMS implementation, a third-party JMS provider, or another non-JMS messaging product, you must configure a MessagingBridge instance. Each MessagingBridge instance defines the source and target destination for the mapping, a message filtering selector, a QOS, transaction semantics, and various reconnection parameters.
Before starting the procedure in this section, refer to the Using the Messaging Bridge to Interoperate with Different WebLogic Server Versions and Domains or Using the Messaging Bridge to Access a Third-Party Messaging Provider sections for specific configuration requirements and guidelines.
To configure a messaging bridge, follow these steps:
Enter a messaging bridge name that is unique across a WebLogic Server domain. |
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Select the source destination from which messages are received by the messaging bridge. Following the example target JMS bridge destination name that was previously suggested for connecting WebLogic Server versions 6.1 and 8.1, you would select the "61to81SourceDestination" name that you created on the JMS Bridge Destination -> Configuration tab. |
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Select the target destination to which messages are sent from the messaging bridge. Following the example target JMS bridge destination name that was previously suggested for connecting WebLogic Server versions 6.1 and 8.1, you would select the "61to81TargetDestination" name that you created on the JMS Bridge Destination -> Configuration tab. |
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Specify a selector to filter the messages that are sent across the messaging bridge. Only messages that match the selection criteria are sent across the messaging bridge. For queues, messages that do not match the selection criteria are left behind and accumulate in the queue. For topics, messages that do not match the connection criteria are dropped. For more information on using selectors to filter messages, see "Developing a WebLogic JMS Application" in Programming WebLogic JMS. |
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Select a QOS guarantee for forwarding a message across a messaging bridge. The valid qualities of service are: Exactly-once—Each message will be sent exactly once. This is the highest quality of service. In order to use this QOS:
Atmost-once—Each message is sent at most one time. Some messages may not be delivered to the target destination. Duplicate-okay—Each message is sent at least one time. Duplicate messages can be delivered to the target destination. |
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Indicate whether the messaging bridge automatically degrades the requested QOS when the configured one is not available. If this occurs, a message is delivered to the WebLogic startup window (or log file). If this option is not selected (false), and the messaging bridge cannot satisfy the requested QOS, it will result in an error and the messaging bridge will not start. |
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For bridges running in asynchronous mode, specify the maximum amount of time, in seconds, the messaging bridge sits idle before checking the health of its connections. For bridges running in synchronous mode, this dictates the amount of time the messaging bridge can block on a receive call if no transaction is involved. |
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Indicate whether a messaging bridge works in asynchronous mode. Messaging bridges that work in asynchronous mode (true) are driven by the source destination. The messaging bridge listens for messages and forwards them as they arrive. When the value is false, the bridge works in synchronous mode even if the source supports asynchronous receiving. Note: For a messaging bridge with a QOS of Exactly-once to work in asynchronous mode, the source destination has to support the MDBTransaction interface described in the weblogic.jms.extensions Javadoc. Otherwise, the bridge automatically switches to synchronous mode if it detects that MDBTransactions are not supported by the source destination. For more information about MDBTransactions, see "Using Message-Driven Beans" in Programming WebLogic EJB. |
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This is used only for JMS topics or for third-party destinations with similar characteristics as a JMS topic. By enabling durability, a messaging bridge creates a durable subscription for the source destination. This allows the source JMS implementation to save messages that are sent to it when the bridge is not running. The bridge will then forward these messages to the target destination once it is restarted. If this attribute is not selected, messages that are sent to the source JMS topic while the bridge is down cannot be forwarded to the target destination. Note: If a bridge must be taken permanently offline, you must delete any durable subscriptions that use the bridge. For information on deleting durable subscribers, see "Deleting Durable Subscriptions" in Programming WebLogic JMS. |
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Indicate the initial state of the messaging bridge (that is, the state when the bridge is booted). The default value is for the bridge to be started. To stop the messaging bridge, clear the check box. Conversely, reselect the check box to restart the bridge. Note: This does not indicate the run-time state of the bridge. For information on monitoring a bridge's state, see Monitoring All Messaging Bridges. |
For more information about the general messaging bridge attributes, see the Attributes table in Messaging Bridge --> Configuration --> General.
For more information about the bridge's connection retry attributes, see the Attributes table in Messaging Bridge --> Configuration --> Connection Retry.
For more information about the bridge's transaction attributes, see the Attributes table in Messaging Bridge --> Configuration --> Transactions.
For more information, see Targeting a Messaging Bridge to a Server, a Cluster, or a Migratable Target.
Targeting a Messaging Bridge to a Server, a Cluster, or a Migratable Target
Note: This must be the same target where the bridge's resource adapter was deployed. For more information, see Deploying the Bridge's Resource Adapters.
Using the Messaging Bridge to Interoperate with Different WebLogic Server Versions and Domains
The following interoperability guidelines apply when using the messaging bridge to access JMS destinations in different releases of WebLogic Server and in other WebLogic domains.
Naming Guidelines for WebLogic Servers and Domains
Unique naming rules apply to all WebLogic Server deployments if more than one domain is involved. Therefore, make sure that:
Enabling Interoperability Security for WebLogic Domains
Follow these guidelines when an 8.1 domain is interoperating with another version 6.1 or later domain:
Note: For more information about interoperability security, see "Using Compatibility Security" in Managing WebLogic Security.
Using the Messaging Bridge To Access Destinations In Another 6.1 or Later Domain
Use these guidelines when configuring a messaging bridge that provides transactional communication between a WebLogic Server 8.1 domain and an earlier WebLogic Server 7.0 or 6.1domain.
Note: The Exactly-once quality of service for transactions is only supported for implementations of WebLogic Server 6.1 or later.
Using the Messaging Bridging To Access Destinations In a 6.0 Domain
When configuring a messaging bridge involves interoperability between WebLogic Server 8.1 and a version 6.0 domain, you must configure the following items on the Weblogic Server 8.1 domain that the bridge is running on:
Note: The Exactly-once QOS for transactions is not supported for WebLogic Server 6.0. For more information on the bridge QOS options, see the Attribute table in Messaging Bridge --> Configuration --> General.
Note: For more information about interoperability security, see "Using Compatibility Security" in Managing WebLogic Security.
Using the Messaging Bridging To Access Destinations In a 5.1 Domain
When configuring a messaging bridge involves interoperability between WebLogic Server 8.1 and version 5.1, you must configure the following on the Weblogic Server 8.1 implementation that the bridge is running on:
Note: The Exactly-once QOS for transactions is not supported for WebLogic Server 5.1. For more information on the bridge QOS options, see the Attribute table in Messaging Bridge --> Configuration --> General.
For example, if you have WebLogic Server 5.1 GA installed in a directory named WL51_HOME and your WebLogic Server 8.1 release is installed in WL81_HOME, then set the Adapter Classpath as follows for the 5.1 destination:
WL51_HOME\classes;WL51_HOME\lib\weblogicaux.jar;
WL81_HOME\server\lib\jms51-interop.jar
Note: For more information about interoperability security, see "Using Compatibility Security" in Managing WebLogic Security.
Using the Messaging Bridge to Access a Third-Party Messaging Provider
When configuring a messaging bridge involves interoperability with a third-party messaging provider, you must configure the following:
For more information on configuring the remaining attributes for a JMS Bridge Destination, see Configuring JMS Bridge Destinations.
Once a messaging bridge is up and running, it can managed from the console.
Monitoring All Messaging Bridges
To monitor the status of all configured messaging bridges in your domain:
Stopping and Restarting a Messaging Bridge
To temporarily suspend and restart an active messaging bridge:
Configuring the Messaging Bridge Execute Thread Pool Size
You can configure the default execute thread pool size for your messaging bridges. For example, you may want to increase or decrease the default size to reduce competition from the WebLogic Server default thread pool. Entering a value of -1 disables this thread pool and forces a messaging bridge to use the WebLogic Server default thread pool.