26 Troubleshooting and Best Practices

This chapter lists a few tips for troubleshooting Coherence and some Coherence best practices. It contains the following sections:

Troubleshooting Coherence

  • Collecting Metric Data: If you cannot collect metric data for any of the Coherence targets, check the following to ensure that the steps involved in discovering the target have been followed correctly.

    • Make sure that the management node has been successfully started and the host on which the management node is running is accessible from the Agent host.

    • Specify the appropriate User Name and Password if password authentication is enabled.

    • If you are not using SSL to start the management node, make sure that you have started the JVM using the com.sun.management.jmxremote.ssl=false option.

  • Dynamic Client Nodes: If there are dynamic client nodes that are not running all the time, these nodes can be removed from the cluster and proxy service can be used.

  • Target Proliferation of Nodes: If there is a target proliferation of nodes, this may be due to NULL or duplicate tangosol.coherence.member value for the nodes. Verify that each node has a nonNull and unique value for the tangosol.coherence.member property.

Best Practices

This section describes some of the best practices that can be used while setting up and using Oracle Coherence. It covers the following:

Monitoring Templates

Monitoring templates for each of the Coherence Cluster, Node, and Cache targets are available out-of-the-box. These templates can be used as default monitoring templates for all Coherence targets. Based on specific requirements, you can enable, disable certain metrics, or change the collection frequency.

Note:

The threshold values provided in the templates are examples and must be changed.