2 Overview of Systems Monitoring

Monitoring Overview

Enterprise Manager monitoring features provide increased out-of-box value, automation, and monitoring support to enable IT organizations to maximize operational efficiencies and provide high quality services. For applications that are built on Oracle, Enterprise Manager offers the most comprehensive monitoring of the Oracle environment. To support the myriad and variety of applications built on Oracle, Enterprise Manager expands its monitoring scope to non-Oracle components, such as third-party application servers, hosts, firewalls, server load balancers, and storage.

Enterprise Manager provides the most comprehensive management features for all Oracle products. For example, Enterprise Manager's monitoring functionality is tightly integrated with Oracle Database manageability features such as server-generated alerts. These alerts are generated by the database itself about problems it has self-detected. Server-generated alerts can be managed from the Enterprise Manager console and include recommendations on how problems can be resolved. Performance problems such as poorly performing SQL and corresponding recommendations that are generated by the database's self-diagnostic engine, called Automatic Database Diagnostic Monitor (ADDM), are also captured and exposed through the Enterprise Manager console. This allows Enterprise Manager administrators to implement ADDM recommendations with ease and convenience.

Adding targets to monitor is simple. Enterprise Mangager provides you with the option of either adding targets manually or automatically discovering all monitorable targets on a host. Once your targets have been added to your monitored environment, Enterprise Manager also makes it easy to expand the scope of enterprise monitoring beyond individual components. Using Enterprise Manager's group management functionality, you can easily organize monitorable targets into groups, allowing you to monitor and manage many components as one. Enterprise Manager can also automatically and intelligently apply monitoring settings for every added target.

Monitoring Basics

Enterprise monitoring functionality permits unattended monitoring of your IT environment. Enterprise Manager comes with a comprehensive set of performance and health metrics that allows monitoring of key components in your environment, such as applications, application servers, databases, as well as the back-end components on which they rely (such as hosts, operating systems, storage).

The Management Agent on each monitored host monitors the status, health, and performance of all managed components (also referred to as targets) on that host. If a target goes down, or if a performance metric crosses a warning or critical threshold, an "event" is created and sent to Enterprise Manager and to Enterprise Manager administrators who have registered interest in receiving such notifications. Enterprise monitoring functionality and the mechanisms that support this functionality are discussed in the following sections.

When it is not practical to have a Management Agent present to monitor specific components of your IT infrastructure, as might be the case with an IP traffic controller or remote Web application, Enterprise Manager provides Extended Network and Critical URL Monitoring functionality. This feature allows the Beacon functionality of the Agent to monitor remote network devices and URLs for availability and responsiveness without requiring an Agent to be physically present on that device. You simply select a specific Beacon, and add key network components and URLs to the Network and URL Watch Lists. More information about using this feature is available in the Enterprise Manager online help and from the Oracle Technology Network Web site.

Out-of-Box Monitoring

Enterprise Manager's Management Agents automatically start monitoring their host's systems (including hardware and software configuration data on these hosts) as soon as they are deployed and started. Enterprise Manager provides auto-discovery scripts that enable these Agents to automatically discover all Oracle components and start monitoring them using a comprehensive set of metrics at Oracle-recommended thresholds. This monitoring functionality includes other components of the Oracle ecosystem such as NetApp Filer, BIG-IP load balancers, Checkpoint Firewall, and IBM WebSphere and Oracle WebLogic application servers. Metrics from all monitored components are stored and aggregated in the Management Repository, providing administrators with a rich source of diagnostic information and trend analysis data. When critical alerts are detected, notifications are sent to administrators for rapid resolution.

Out-of-box, Enterprise Manager monitoring functionality provides:

In-depth monitoring with Oracle-recommended metrics and thresholds.
Montioring of all components of your IT infrastructure (Oracle and non-Oracle) as well as the applications and services that are running on them.
Access to real-time performance charts.
Collection, storage, and aggregation of metric data in the Management Repository. This allows you to perform strategic tasks such as trend analysis and reporting.
E-mail and pager notifications for detected critical events.

Enterprise Manager can monitor a wide variety of components (such as databases, hosts, and routers) within your IT infrastructure.

Some examples of monitored metrics are:

Archive Area Used (Database)
Component Memory Usage (Application Server)
Segments Approaching Maximum Extents Count (Database)
Network Interface Total I/O Rate (Host)

Some metrics have associated predefined limiting parameters called thresholds that cause alerts to be triggered when collected metric values exceed these limits. Enterprise Manager allows you to set metric threshold values for two levels of alert severity:

Warning - Attention is required in a particular area, but the area is still functional.
Critical - Immediate action is required in a particular area. The area is either not functional or indicative of imminent problems.

Hence, thresholds are boundary values against which monitored metric values are compared. For example, for each disk device associated with the Disk Utilization (%) metric, you might define a warning threshold at 80% disk space used and critical threshold at 95%.

Monitoring Templates

Monitoring templates simplify the task of standardizing monitoring settings across your enterprise by allowing you to specify the monitoring settings once and apply them to your monitored targets. This makes it easy for you to apply specific monitoring settings to specific classes of targets throughout your enterprise. For example, you can define one monitoring template for test databases and another monitoring template for production databases.

A monitoring template defines all Enterprise Manager parameters you would normally set to monitor a target, such as:

Target type to which the template applies.
Metrics (including user-defined metrics), thresholds, metric collection schedules, and corrective actions.

When a change is made to a template, you can reapply the template across affected targets in order to propagate the new changes. You can reapply the monitoring templates as often as needed. For any target, you can preserve custom monitoring settings by specifying metric settings that can never be overwritten by a template.

Comparing Differences Between Targets and Monitoring Templates

Deciding how and when to apply a template is simplified by using the Compare Monitoring Template feature. This feature allows you to see at a glance how metric and policy settings defined in a template differ from those defined on the destination target. Compare Monitoring Template is especially useful when working with aggregate targets such as groups and systems. For example, after you apply a Monitoring Template to a group, you want to verify that the group members now have the same monitoring settings as the template. The Compare Monitoring Template feature makes checking simple. You can also schedule this as a report, allowing you to check periodically if the group members still follow the template settings.