Setting up the data store for a messaging engine

The database administrator and WebSphere Process Server administrator need to set up a data store for each messaging engine of the SCA runtime.

Why and when to perform this task

Before you can deploy a mediation module into WebSphere Process Server, you must have configured a server or server cluster to host destinations for the SCA runtime required. This advanced configuration adds the server or cluster as a member of the SCA.SYSTEM bus, and configures the messaging engine for the server or cluster on that bus. If you perform the JMS element of SCA configuration for a server or cluster, a second messaging engine is created for the SCA.APPLICATION bus. Each messaging engine requires a separate database or schema to be created.

Each messaging engine has its own data store to store persistent data in a database. All the tables in the data store are held in the same database schema. You can create each data store in a separate database. Alternatively, you can create multiple data stores in the same database, with each data store using a different schema.

A messaging engine uses an instance of a JDBC data source to interact with the database that contains the data store for that messaging engine.

Before configuring a server cluster to host destinations for the SCA runtime, you must configure both the data store and the JDBC data source that the messaging engine uses to interact with its data store.

If you configure a server to host destinations for the SCA runtime, the messaging engine is configured to use a Cloudscape data source by default. This default configuration enables the messaging engine to run without needing any additional configuration by the Administrator. If you do not want to use the default data source configuration, you can change the configuration parameters. For example, you can change the data source or you can configure the data store to use a different JDBC provider.

To set up the data store for a messaging engine, complete the following steps. These steps are the same as for the underlying WebSphere Application Server, and link to WebSphere Application Server topics for more information.

Steps for this task

  1. Ask your database administrator to perform the following steps:
    1. Create the database. Choose which relational database management system (RDBMS) you want to use for the data store. Unless you want a server to use the default Cloudscape provider, create the database before you configure a server to host destinations for the SCA runtime. Refer to the documentation for your chosen RDBMS for information about how to create a database.

      The default database name for SCA messaging engines is SCADB.

    2. Create users and schemas. The default schema name is IBMWSSIB.

      If your database type does not support multiple schemas in the same database instance, you must configure a separate database instance for each messaging engine.

      For more information about creating users and schemas, see Creating users and schemas in the database.

    3. Create the data store tables. Decide whether you want your database administrator to create the tables, or you want to allow WebSphere to create the tables automatically. To create the tables automatically, ensure that WebSphere Process Server has sufficient authority to create tables and indexes. Later, when you configure your messaging engine, you indicate that its tables should be created automatically.

      For more information about creating data store tables for a messaging engine, see Creating the tables

    4. Create a database user ID with sufficient privilege to access the data store. A messaging engine uses a database user ID to authorize access to its data store tables. The user ID must have the authority to be able to create tablespaces, tables, indexes, and stored procedures for the data store.

      For more information about the privileges that you require for your chosen database, see Database privileges.

  2. Perform the following steps:
    1. Obtain the database user ID from your database administrator.
    2. Configure a JDBC data source. The following naming convention is used for the JDBC data source that the messaging engine uses to interact with the database:
      • SCA.SYSTEM bus: nodeserver|cluster-SCA.SYSTEM_bus_name
      • SCA.APPLICATION bus: nodeserver|cluster-SCA.APPLICATION_bus_name
      For a messaging engine in a server cluster, the data store configuration depends on the purpose of the cluster:
      • For workload sharing, every messaging engine must have its own data store.
      • For failover, you must have one data store for all of the messaging engines in the failover cluster. When a messaging engine runs in a failover cluster, its data store must be accessible from every server that can potentially run the messaging engine that owns the data store.
      When a messaging engine is created as a member of a cluster, you must explicitly configure both the data store and the JDBC data source that the messaging engine uses to interact with the data store:
      • If each messaging engine has its own JDBC data source, you can create the data sources at node scope.
      • If several messaging engines share the same JDBC data source, you must create the data source at cluster scope, not node scope.
      You must also ensure that you install the JDBC driver jars at every node on which a cluster member runs.

      For more information about configuring a data source, see Configuring a JDBC data source.


Last updated: Wed 06 Dec 2006 07:08:08

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