6.15.2. Setting up Multicast Detection
Multicast detection uses JBoss's Remoting framework, which allows the agent to detect whenever a server comes on or goes off line within a few seconds. Using the Remoting framework requires support for multicast traffic; otherwise, the agent cannot detect the server. This has more configuration parameters than simple polling:
- Setting to enable both server detection and multicast traffic (
rhq.agent.server-auto-detectionandrhq.communications.multicast-detector.enabled, respectively). - A wait interval between server communications (
rhq.communications.multicast-detector.default-time-delay); if the server is silent longer than that interval, then the server is considered offline. - Await, or heartbeat, interval for the agent's own messages (
rhq.communications.multicast-detector.heartbeat-time-delay). This value must be shorter than the JBoss ON server's heartbeat interval (rhq.communications.multicast-detector.default-time-delay), or it results in unnecessary messages and network traffic.
To enable multicast detection:
- Open the agent prompt. For example, if the agent process is already running, the prompt can be opened by re-running the
rhq-agent.shscript with the-noption.agentRoot/rhq-agent/bin/rhq-agent.sh -n
- Send the
setconfigwith the multicast settings. The time-delay values are in milliseconds.> setconfig rhq.agent.server-auto-detection=true > setconfig rhq.communications.multicast-detector.enabled=true > setconfig rhq.communications.multicast-detector.default-time-delay=75000 > setconfig rhq.communications.multicast-detector.heartbeat-time-delay=60000
- Restart the agent process to load the new configuration.
agentRoot/rhq-agent/bin/rhq-agent-wrapper.sh stop agentRoot/rhq-agent/bin/rhq-agent.sh
