 | ||
| How intelligent resource monitoring works | ||
|---|---|---|
| Prev | About resource monitoring | Next |
When an IMF-aware agent starts up, the agent initializes with the IMF notification module. After the resource moves to a steady state, the agent registers the details that are required to monitor the resource with the IMF notification module. For example, the process agent registers the PIDs of the processes with the IMF notification module. The agent's imf_getnotification function waits for any resource state changes. When the IMF notification module notifies the imf_getnotification function about a resource state change, the agent framework runs the monitor agent function to ascertain the state of that resource. The agent notifies the state change to VCS which takes appropriate action.
A resource moves into a steady state when any two consecutive monitor agent functions report the state as ONLINE or as OFFLINE. The following are a few examples of how steady state is reached.
When a resource is brought online, a monitor agent function is scheduled after the online agent function is complete. Assume that this monitor agent function reports the state as ONLINE. The next monitor agent function runs after a time interval specified by the MonitorInterval attribute. If this monitor agent function too reports the state as ONLINE, a steady state is achieved because two consecutive monitor agent functions reported the resource state as ONLINE. After the second monitor agent function reports the state as ONLINE, the registration command for IMF is scheduled. The resource is registered with the IMF notification module and the resource comes under IMF control.The default value of MonitorInterval is 60 seconds.
A similar sequence of events applies for taking a resource offline.
Assume that IMF is disabled for an agent type and you enable IMF for the agent type when the resource is ONLINE. The next monitor agent function occurs after a time interval specified by MonitorInterval. If this monitor agent function again reports the state as ONLINE, a steady state is achieved because two consecutive monitor agent functions reported the resource state as ONLINE.
A similar sequence of events applies if the resource is OFFLINE initially and the next monitor agent function also reports the state as OFFLINE after you enable IMF for the agent type.