WebSphere Commerce EnterpriseWebSphere Commerce Professional

Clustering with horizontal cluster members

After you federate your WebSphere Commerce environment, you can configure horizontal clustering. Clustering provides failover protection and provides workload balancing.Clustering with horizontal cluster members refers to the traditional practice of defining cluster members of an application server on multiple physical machines. This process allows a single application to span several machines while presenting a single system image. Clustering with horizontal cluster members can provide increased throughput and high availability.

Before you begin

  1. Complete the installation of a WebSphere Commerce node.
  2. Create a WebSphere Commerce instance.
  3. Before you cluster a WebSphere Commerce instance, back up the WebSphere Application Server administrative configuration. If clustering fails during the clustering process, you can restore the original configuration.

Procedure

To create a cluster with horizontal cluster members:
  1. Federate the WebSphere Commerce node into a deployment manager cell.
  2. Prepare additional nodes for each node that you want to add to the cluster.
  3. Define the JDBC provider path for each node that contains a server that is or will be a member of the WebSphere Commerce cluster.
  4. Create a WebSphere Commerce Cluster.
  5. Adding additional cluster members if required.
  6. Start the WebSphere Application Server administration server.
  7. Launch the WebSphere administrative console.
  8. Create an Internal Replication Domain for your application:
    Note: It is possible to create this as part of the initial cluster setup. If you have already created a Replication Domain for your application, you can use the existing one.
    1. Click Environment > Replication domains > New.
    2. Fill in the required fields. For Number of replicas, select Entire Domain. Save the changes.
  9. Enable cache replication in each cluster member.
    1. Click Servers > Application servers > Cluster Member Name > Container Services > Dynamic Cache Service.
    2. To enable replication, select Enable Cache Replication.
    3. Choose a replication domain.
    4. Choose a replication type. For WebSphere Commerce, the recommendation is to use Not shared. For other options, see Dynamic cache service settings.
      Note: With the Not shared replication type, invalidations are sent without replicating content.
    5. Repeat steps a-d for each cluster member.
    6. Save your changes.
  10. Ensure the replication domain and replication type of all out of box DistributedMap object caches are specified.
    1. Open the WebSphere Application Server Integrated Solutions Console.
    2. From the left menu, click Resources > Cache instances > Object cache instances.
  11. Ensure that the replication domain and a replication type of 1 (not-shared) is specified for all of the object caches that are defined in the Stores.war/classes/cacheinstances.properties file. The object cache with the JNDI name services/cache/WCSessionDistributedMapCache must be defined. For more information see Enabling WebSphere Commerce data cache.
  12. Instead of using a default setting, always explicitly specify the replication mode for each entry in cachespec.xml.
    For example:
    • Add <sharing-policy>shared-push</sharing-policy> to each cache-entry in cachespec.xml.
      Note: You can choose not to replicate certain cache entries. To configure a cache entry to not replicate, set <sharing-policy>not-shared</sharing-policy>. See the cachespec.xml.

      For more information, see Cache replication.

  13. Regenerate the Web server plug-in and copy the plug-in to the Web server.

    Ensure that the web server configuration file, httpd.conf, points to right web server plug-in file.

  14. Start your WebSphere Commerce cluster.