JBoss Nagios MBean

Description

The JBoss Nagios MBean opens a port on your server for a simple Nagios plugin to connect to. It provides the ability to monitor any JMX attribute, use alarm ranges, calculate deltas on counters and even monitor singletons in a cluster.

Download

Both, the JBoss Nagios MBean and the Nagios plugin can be obtained from the jboss2nagios project.

JBoss Nagios Plugin

Description

The JBoss Nagios Plugin is a simple bash script that uses Twiddle to read targeted numerical JMX attributes such as connections in use, thread counts or JVM heap sizes.

Implementation

• Copy the attached script to your Nagios plugin directory. (RPM installs put it here: /usr/lib/nagios/plugins)

• Issue a chmod 755 check_jbossjmx to make the file executable.

• Add the following entry into the nagios

 # 'check_jbossjmx' command definition 
define command{ 
        command_name    check_jbossjmx 
        command_line    /usr/lib/nagios/plugins/check_jbossjmx $HOSTADDRESS$ $ARG1$ $ARG2$ $ARG3$ $ARG4$ $ARG5$ 
        } 

• Now implement a service check for a server. (Note that this implementation assumes JNDI listening on port 1099). Example:

define service{ 
        use                             generic-service         ; Name of service template to use 
        host_name                       MY_JBOSS_SERVER 
        service_description             CHECK_ORACLE_POOL_SIZE 
        is_volatile                     0 
        check_period                    24x7 
        max_check_attempts              3 
        normal_check_interval           5 
        retry_check_interval            1 
        passive_checks_enabled          0 
        contact_groups                  OpsGroup 
        notification_interval           120 
        notification_period             24x7 
        notification_options            c,r,w 
        check_command                   check_jbossjmx!3!"jboss.jca:name=ORACLEDSN,service=ManagedConnectionPool"!InUseConnectionCount!20!50 
}

This example will use JBoss 3's twiddle to check the connections in use on the app server. If the count is 50 or greater, it will generate a critical alert. If the count is 20 or greater, it will generate a warning alert.

Reference

There are three settings you must configure in the checkjbossjmx_ script:

1. JAVA_HOME:Set this to the Java Home of the JVM you want to use.

2. JBOSS4_HOME: Set this to the JBossHome of a JBoss4 installation. Twiddle will be located as $JBOSS4_HOME/bin/twiddle.sh

3. JBOSS3_HOME: Set this to the JBossHome of a JBoss3 installation. Twiddle will be located as $JBOSS3_HOME/bin/twiddle.sh

Note that you only have JBoss 3 or only JBoss 4 servers, you do not need to configure both.

The parameters to the plugin can be viewed by invoking check_jbossjmx --help.

The parameters are as follows:

1. The JBoss IP Address. (If the JNDI port is not 1099, there is an additional bit of poking around you need to do)

2. The JBoss version. 3 or 4

3. The full object name of the target MBean.

4. The attribute name

5. The warning threshhold

6. The critical threshhold