The CHECK_JMX plugin

The CHECK_JMX plugin, is a powerful tool that allows the execution of JMX queries. It supports the following parameters:

  • -U/--url: JMX URL, for example: 'service:jmx:rmi:///jndi/rmi://localhost:1616/jmxrmi'
  • -O/--object: Object name to be checked, for example, 'java.lang:type=Memory'
  • -A/--attribute: Attribute of the object to be checked, for example, 'NonHeapMemoryUsage'
  • -K/--attributeKey: Attribute key for -A attribute compound data, for example, 'used'
  • -I/--infoattribute: Attribute of the object containing information for text output
  • -J/--infokey: Attribute key for -I attribute compound data, for example, 'used'
  • -w/--warning: Warning range
  • -c/--critical: Critical range
  • -u/--username: monitorRole jmx username
  • -p/--password: monitorRole jmx password

Usage Example

The following example shows how to monitor the memory usage of a JBOSS application server.

To configure the check, we can use both the XML or the INI configuration file.

Configuring using the XML configuration style

  <command name="CHECK_JBOSS_JMX" plugin_name="CHECK_JMX">
     <arg name="url"  value="service:jmx:remoting-jmx://$ARG1$" />
     <arg name="object"  value="java.lang:type=Memory" />
     <arg name="attribute"  value="HeapMemoryUsage" />
     <arg name="warning"  value="$ARG2$" />
     <arg name="critical"  value="$ARG3$" />
  </command>

 <<Warning!!>> The url specified works only with JBOSS version 7.1 or greater. For older versions, please refer to the
 jboss manual.

Configuring using the INI configuration style

  CHECK_JBOSS_MEM : CHECK_JMX --url service:jmx:remoting-jmx://$ARG1$ --object java.lang:type=Memory --attribute HeapMemoryUsage -K used --warning $ARG2$ --critical $ARG3$

Warning!! The url specified works only with JBOSS version 7.1 or greater. For older versions, please refer to the jboss manual.

Any of the parameters ($ARG?$ macros) could be hardcoded inside the JNRPE configuration.

Invocation

Warning!! To work with JBOSS version 7.1 or greater, the jboss-client.jar must be put inside the same directory of the CHECK_JMX plugin JAR file.

With the following invocation example we will rise a warning if the memory is beyond 50.000.000 bytes and a critical if it is beyond 70.000.000 bytes.

  check_nrpe -n -H 127.0.0.1 -c CHECK_JBOSS_MEM -a localhost:9999 50000000 70000000