How plug-ins work
We learnt in Chapter 1,Enterprise Manager Grid Control, about targets, target metadata, and target collection file. Target is an entity managed by the Enterprise Manager Grid Control. For each target type there is a target metadata file that defines the properties for the target, the metrics that need to be collected for a target and the mechanism to collect those metrics. For each target type there is a collection file that defines at what frequency metrics should be collected and at what frequency metrics should be persisted. You may want to revisit Chapter 3, Enterprise Manager Key Concepts and Subsystems, before we continue with this chapter. Once you have familiarized yourself about the purpose of these entities, let's use them to see how plug-ins work.
Plug-in artefacts
There are two types of artefacts for a plug-in:
1. Mandatory artefacts: Target metadata and Target collection are the mandatory artefacts; with these artefacts all of the monitoring metrics can be collected...
