How to Use This Manual

The Oracle Enterprise Manager Oracle Virtual Infrastructure Metric Reference Manual (hereafter referred to as the Oracle Virtual Infrastructure Metric Reference Manual) lists all the Oracle Virtual Infrastructure target metrics that Enterprise Manager monitors.

This preface describes:

Structure of This Manual

This manual contains a chapter for each target for which there are metrics.

The metrics in each chapter are in alphabetical order according to category.

Metric Information

The information for each metric comprises a description, summary of the metric's "vital statistics", data source (if available), and user action. The following list provides greater detail:

Description

Explanation following the metric name. This text defines the metric and, when available, provides additional information pertinent to the metric.
Metric Summary

Explains in table format the target version, collection frequency, default warning threshold, default critical threshold, and alert text for the metric.
Data Source

How the metric is calculated. In some metrics, data source information is not available.
User Action

Suggestions of how to solve the problem causing the alert.

Examples of Metric Summary Tables

This section provides examples of Metric Summary tables you will see in this guide.

When default thresholds are not defined for a metric, only the target version and collection frequency are available.

Target Version	Collection Frequency
All Versions	Every 15 Minutes

Definitions of Columns in Metric Summary Tables

As previously mentioned, the Metric Summary table is part of the overall metric information. The following table provides descriptions of columns in the Metric Summary table.

Column Header	Column Definition
Target Version	Version of the target, for example, 9.0.2.x and 10.1.0.x. The x at the end of a version (for example, 9.0.2.x) represents the subsequent patchsets associated with that release.
Collection Frequency	The rate at which the Management Agent collects data. The collection frequency for a metric comes from the Enterprise Manager default collection file for that target type.
Default Warning Threshold	Value that indicates whether a warning alert should be initiated. If the evaluation of the warning threshold value returns a result of TRUE for the specified number of consecutive occurrences defined for the metric, an alert triggers at the warning severity level.
Default Critical Threshold	Value that indicates whether a critical alert should be initiated. If the evaluation of the critical threshold value returns a result of TRUE for the specified number of consecutive occurrences defined for the metric, an alert triggers at the critical severity level.
Alert Text	Message indicating why the alert was generated. Words that display between percent signs (%) denote variables. For example, `Disk Utilization for %keyValue% is %value%%` could translate to `Disk Utilization for d0 is 80%`.

Background Information on Metrics, Thresholds, and Alerts

An event is a significant occurrence on a managed target that typically indicates something has occurred outside normal operating conditions, such as a performance threshold violation, an unapproved change in application configuration files, or job failure. An event can also be raised to signal successful operations or a job successfully completed.

Existing Enterprise Manager customers may be familiar with metric alerts and metric collection errors. For Enterprise Manager 13c, metric alerts are a type of event. A metric alert event is generated when an alert occurs for a metric on a specific target (Example: CPU utilization for a host target) or a metric on a target and object combination (Example: Space usage on a specific tablespace of a database target.)

Thresholds are boundary values against which monitored metric values are compared. For example, for each disk device associated with the Disk Utilization (%) metric, you can define a different warning and critical threshold. Some of the thresholds are predefined by Oracle, others are not.

When a threshold is reached, an alert is generated. This alert is an indicator signifying that a particular condition has been encountered and is triggered when one of the following conditions is true:

A threshold is reached.
An alert has been cleared.
The availability of a monitored service changes. For example, the availability of an application server changes from up to down.
A specific condition occurs. For example, an alert is triggered whenever an error message is written to a database alert log file.

Alerts are detected through a polling-based mechanism by checking for the monitored condition from a separate process at regular, predefined intervals.

Editing

Out of the box, Enterprise Manager comes with thresholds for critical metrics. Warning and critical thresholds are used to generate an alert, letting you know of impending problems so that you can address them in a timely manner.

To better suit the monitoring needs of your organization, you can edit the thresholds provided by Enterprise Manager and define new thresholds. When defining thresholds, the key is to choose acceptable values to avoid unnecessary alerts, while still being notified of issues in a timely manner.

You can establish thresholds that will provide pertinent information in a timely manner by defining metric baselines that reflect how your system runs for a normal period of time.

The metrics listed on the Edit Thresholds page are either default metrics provided by Oracle or metrics whose thresholds you can change.

Specifying Multiple Thresholds

The Specifying Multiple Thresholds functionality allows you to define various subsets of data that can have different thresholds. By specifying multiple thresholds, you can refine the data used to trigger alerts, which are one of the key benefits of using Enterprise Manager. The key in specifying multiple thresholds is to determine how the comparison relates to the metric threshold as a whole. What benefit will be realized by defining a more stringent or lax threshold for that particular device, mount point, and so on. For example, using the Average Disk I/O Service Time metric, you can define warning and critical thresholds to be applied to all disks (sd0 and sd1), or you can define different warning and critical thresholds for a specific disk (sd0). This allows you to adjust the thresholds for sd0 to be more stringent or lax for that particular disk.

Accessing Metrics Using the Cloud Control Console

To access metrics in the Cloud Control Console, use the All Metrics page associated with a particular target by doing the following:

From the Cloud Control Console, choose the target.
On the target's home page, click All Metrics in the Related Links section.
On the All Metrics page, choose the metric of interest.