The core group bridge service can be configured for communication between core groups. Use an access point group to define the core groups that communicate. Use this task to configure communication between core groups that are in different cells.
Use the core group bridge service to share the availability status of the servers in each core group among all the configured core groups. Enable the core group bridge only when the service is required by a WebSphere Application Server component.
For example, the core group bridge is required when configuring an Enterprise JavaBeans (EJB) backup cluster. Configure a backup EJB cluster in a different cell to continue servicing requests when the primary cluster fails. See Creating backup clusters for more information.
When you configure core group communication between core groups that are in different cells, you must configure an access point group to connect the core groups. The name of the access point group must be the same in all of the connected cells. This task uses the DefaultAccessPointGroup access point group, but you can create and use another access point group.
With WebSphere Application Server, Version
6.0.2 or later, you can define the CGB_ENABLE_602_FEATURES custom property
on all of the access point groups in your configuration if you want to be
able to add core group bridge servers to the configuration without restarting
the other servers in the configuration. After you enable this property, you
can add a core group bridge server in one cell, without modifying the configuration
in the other cell to include peer ports for the core group bridge server.
Instead of manually configuring peer ports in each of the cells, you can configure
the peer ports in one cell and let the other cell discover the peer ports
for the first cell.
If
you decide to use the CGB_ENABLE_602_FEATURES custom property, you must decide
which cell is the listener cell and which cell initiates contact with the
other cells before you begin your configuration. The listener cell does not
need to contain any peer access points or peer ports for the other cells in
the configuration. For example, in a configuration that contains a secured
cell and an unsecured cell, configure the unsecured cell as the listener.
The unsecured cell cannot access information about the secured cell. Configure
the core group bridge service on the listener cell first.
Complete the following set of steps for each of the cells in your configuration.
The following illustration is an example of a configuration between two core groups that are in two different cells. Each cell has a defined DefaultAccessPointGroup access point group, which contains one core group access point for the core group that is in the cell and a peer access point for the other cell.