User-Defined Metric Example

The sample Perl script used in this example monitors the 5-minute load average on the system. The script performs this function by using the uptime command to obtain the average number of jobs in the run queue over the last 5 minutes.

The script is written in Perl. Enterprise Manager uses the system variables %perlBin% to obtain the location of the Perl interpreter and %scriptsDir% to obtain the location of the script. Both of these variables are defined in the emd.properties file.

This script, called udmload.pl, is installed in a common administrative script directory (%scriptsDir% = $ORACLE_ HOME/admin_scripts).

Important: Do not store user-defined metric monitoring scripts in the same location as Enterprise Manager system scripts.

Setting Up the Sample Script as a User-Defined Metric

  1. Copy the script (udmload.pl) to the monitored target. For example: $ORACLE_ HOME/admin_scripts. Make sure you have an Enterprise Manager 10g Management Agent running on this machine.

  2. Edit the script, if necessary, to point to the location of the Perl interpreter on the monitored target. By default, the script assumes the Perl interpreter is in /usr/local/bin.

  3. As a test, run the script: udmload.pl You may need to set its file permissions so that it runs successfully. You should see output of this form:

    em_result=2.1
  4. In Create User-Defined Metric page, create a new user-defined metric as follows:

    Definition Settings

    Metric Name: Test User-Defined Metric

    Metric Type: Number

    Command Line: %perlBin%/perl %scriptsDir%/udmload.pl

    Environment: leave blank

    Operating System User Name: <OS user able to execute the script>

    Password: ******

    Threshold Settings

    Comparison Operator: >=

    Critical Threshold: 0.005

    Warning Threshold: 0.001

    Consecutive Occurrences Preceding Notification: 1

    In this example, we want the metric to trigger an alert at a Warning level if the 5-minute load average on the machine reaches 0.005, and trigger an alert at a Critical level if the 5-minute load average reaches 0.001. Feel free to change these thresholds depending on your system.

    Schedule Settings:

    Start: Immediately after creation

    Frequency: Repeat every 5 minutes

    Note: You must specify at least a 5 minute interval

When the 5-minute load reaches at least 0.001, you should see the metric trigger an alert.

 

Related Topics

About User-defined Metrics

Creating Your Monitoring Script

Registering the Script as a User-Defined Metric

Enterprise Manager Information Roadmap

Copyright © 1996, 2007, Oracle. All rights reserved.