Configure the core group bridge between core groups that are in different cells

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. Make sure that:

• You have two or more core groups that are in different cells. Core groups are a statically defined component of the high availability manager.

• Any cell that uses core group bridges to connect to core groups in other cells have a name that is unique when compared to the names of the other cells.

• Any core group that uses a core group bridge is configured with Channel framework as its transport mechanism.

Overview

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, 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.

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, 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. Attention: Do not configure the CGB_ENABLE_602_FEATURES custom property if you already configured the FW_PASSIVE_MEMBER custom property. Any server for which the configured the FW_PASSIVE_MEMBER custom property is configured cannot initiate contact with other systems in the configuration. For more information about the FW_PASSIVE_MEMBER custom property, see Core group bridge custom properties.

Complete the following set of steps for each of the cells in your configuration.

Procedure

1. Configure bridge interfaces for your core group access point. Configuring a bridge interface indicates that the specified node, server, and chain combination is a core group bridge server. This node and server use the specified chain to communicate with other core groups.

   1. In the administrative console, click Servers > Core groups > Core group bridge settings > Access point groups > DefaultAccessPointGroup > Core group access points > CGAP_1\DefaultCoreGroup > Show detail > Bridge interfaces > New.

   2. Select a node, server, and transport channel chain that becomes your bridge interface.

   3. Click Apply.

   4. Repeat this set of steps to add more bridge interfaces to the core group access point. Define at least two bridge interfaces for each core group access point to back up your configuration. By defining two bridge interfaces, you define two core group bridge servers. If one core group bridge server fails, the other can take over the work so that the communication between the core groups can continue.

      The bridge interfaces that you select must all have the same transport channel chain.

2. If you want the ability to add core group bridge servers to the configuration without restarting the other servers in the configuration, define the CGB_ENABLE_602_FEATURES custom property on all of the access point groups in your configuration.

   1. In the administrative console, click Servers > Core groups > Core group bridge settings > Access point groups > DefaultAccessPointGroup > Custom properties > New.

   2. Type the name as CGB_ENABLE_602_FEATURES and set the value to any string.

      The existence of the CGB_ENABLE_602_FEATURES property enables the property. Therefore, you can set the value to any string value. Setting the value to false does not disable the property. To disable the property, remove it from the list of defined custom properties or change its name.

   3. Click Apply and save your configuration.

   When you complete this step on all the access point groups in your configuration, you can add a bridge interface to one of the cells. You can save the configuration so that it is propagated to all of the nodes. Instead of restarting all of the application servers, you need to restart the new bridge interface server only.

3. Add peer access points and peer ports to your access point group.

   If you defined the CGB_ENABLE_602_FEATURES custom property for all of the access point groups in your configuration, you do not need to add peer access points or peer ports to the listener cell. Add a peer access point for each core group that is in another cell. Within each peer access point, you should configure a peer port that corresponds to each bridge interface in the other cell. Before you add a peer access point, you should have the following information about the other cell:

   • cell name

   • core group name

   • core group access point name

   • host and port information. The host and port correspond to the bridge interfaces that are configured in the other cell. Specify a peer port for each bridge interface that is in the other cell.

   1. In the administrative console, click Servers > Core groups > Core group bridge settings > Access point groups > DefaultAccessPointGroup > Peer access points > New.

   2. Specify the information for your peer access point and click Next.

   3. Select Use peer ports. Specify the host and port information for your peer cell. For example, if you defined a bridge interface in cell_x, use that configuration information for your peer port in cell_y.

   4. Click Next and then Finish. Save your configuration.

   If more than one bridge interface is defined in your peer cell, add additional peer ports for each bridge interface.

   1. Click Peer_access_point_name > Show detail > Peer ports > New.

   2. Enter the host name and port.

   3. Click Apply and save your changes.

Results

Example

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.

What to do next

Related concepts

Related tasks

Related Reference