Modify a WebSphere MQ link
We can modify a WebSphere MQ link using the dmgr console as described in this task, or we can modify a WebSphere MQ link using wsadmin.
We have to know the name of the bus, and the messaging engine on the bus containing the WebSphere MQ link to modify. A WebSphere MQ link provides a server to server channel connection between a service integration bus and a WebSphere MQ queue manager or queue-sharing group, which acts as the gateway to the WebSphere MQ network. At any time after you create a new WebSphere MQ link, we can modify its properties.
When we use the foreign bus connection wizard to connect a bus and a WebSphere MQ queue manager (gateway queue manager) to use point-to-point messaging or publish-subscribe messaging, one or more WebSphere MQ links are created and configured as part of the task. However the wizard does not ask you to set all possible properties of a WebSphere MQ link, and some of the link properties are not set or are set to default values. We can fine tune these properties by modifying the link.
When creating a new WebSphere MQ link, we can also choose not to create sender or receiver channels. These channels can be added later by modifying the link.
When we use the foreign bus connection wizard to create a WebSphere MQ link for point-to-point messaging, we can later modify the link for publish-subscribe messaging by adding a publish/subscribe broker profile to the link.
- In the navigation pane, click...
Service integration -> Buses -> bus_name -> [Topology] Messaging engines -> engine_name -> [Additional properties] WebSphere MQ links -> link_name
- Modify the properties of the link.
When creating a new WebSphere MQ link, the following properties are set to default values:
- Description
- An optional description for the WebSphere MQ link, for administrative purposes.
- Adoptable
- Whether or not a running instance of a WebSphere MQ link receiver channel (associated with this MQ link) should be adopted or not. In the event of a communications failure, it is possible for a running instance of a WebSphere MQ link receiver channel to be left waiting for messages. When communication is re-established, and the partner WebSphere MQ sender channel next attempts to establish a session with the WebSphere MQ link receiver channel, the request will fail as there is already a running instance of the WebSphere MQ link receiver channel that believes it is in session with the partner WebSphere MQ sender channel. We can overcome this problem by selecting this option, which causes the already running instance of the WebSphere MQ link receiver channel to be stopped and a new instance to be started. By default, this option is not selected.
- Exception destination
- The destination for an inbound message when the WebSphere MQ link cannot deliver the message to its target bus destination, or to the exception destination configured for that target destination, or when the target destination does not exist. By default, undeliverable messages are sent to the system default exception destination for the messaging engine that this link is assigned to. However, it can aid problem-solving if you separate these exceptions out from other system messages by configuring a specific exception destination for this link.
- Initial state
- Whether the WebSphere MQ link is started or stopped when the hosting messaging engine is first started. Until started, the WebSphere MQ link is unavailable. By default, the value is "Started".
- Nonpersistent message speed
- The class of service for nonpersistent messages on channels of this WebSphere MQ link. By default, the value is "Fast".
- Configure the additional properties. We can configure any of the following additional properties of this WebSphere MQ link:
- Configure the related items. We can configure any of the following related items of this WebSphere MQ link:
- Save changes to the master configuration.
- If we have enabled dynamic configuration updates, the changes take effect immediately (or on channel restart if you also modified WebSphere MQ link sender or receiver channels), otherwise restart the application server.
Subtopics
- Add or modify a publish/subscribe broker on the WebSphere MQ link
A publish/subscribe broker profile, and associated topic mappings, allows publication and subscription with a broker in a WebSphere MQ network. We can use the dmgr console to define a broker profile on a WebSphere MQ link, forming a publish/subscribe bridge with a WebSphere MQ network.
- Add or modify a WebSphere MQ link receiver channel
How we can define the properties of the receiver channel on a WebSphere MQ link. This channel receives messages from the WebSphere MQ queue manager or queue-sharing group (known as the "gateway queue manager"). The receiver channel communicates with a WebSphere MQ sender channel on the gateway queue manager, and converts MQ format messages to service integration bus messages.
- Add or modify a WebSphere MQ link sender channel
The WebSphere MQ link sender channel sends messages to the WebSphere MQ queue manager or queue-sharing group (known as the "gateway queue manager"). The sender channel communicates with a WebSphere MQ receiver channel on the gateway queue manager, and converts service integration bus messages to MQ format messages. Use this task to add a sender channel if you have not already defined one, or to fine tune the properties of an existing sender channel.