Hot-Swap Mechanism in J2EE Agents

Most J2EE agent properties are hot-swap enabled. Properties are identified as hot-swappable or not in OpenSSO Enterprise Console (a centralized agent configuration option) and in the OpenSSOAgentConfiguration.properties file (the local agent configuration option). When changes are made to the agent configuration, the changes must be communicated to the property configuration cache for it to be updated. Hot-swap enabled (or Hot-swappable) properties allow such changes to be made without having to restart the agent server. For properties that are not hot-swappable, the new values are only picked up by the agent once the agent container is restarted.

Therefore, when hot-swappable properties are changed on the OpenSSO Enterprise server (using OpenSSO Enterprise Console or the ssoadm utility), the changes can be communicated using notifications or polling. However, when the agent configuration is stored with the agent locally (in the OpenSSOAgentConfiguration.properties), changes to the property values can only be communicated through polling. The communication of property value changes results in an update to the property configuration cache.

For notifications, the property that controls the hot-swap mechanism is labeled Agent Configuration Change Notification (Tab: Global, Name: com.sun.identity.agents.config.change.notification.enable) and for polling, the property that controls the hot-swap mechanism is labeled Configuration Reload Interval (Tab: Global, Name: com.sun.identity.agents.config.load.interval). These two properties, which both control the hot-swap mechanism, are themselves hot-swap enabled. This means that if the hot-swap mechanism is enabled by one of these properties and you change the value of the respective property, the new value will take effect.