Monitoring Tomcat

Monitoring of a running Tomcat instance can be done in several ways, but observing a Tomcat instance via JMX beans will give you the best information available through standard interfaces (i.e. JMX). You can find information about connecting to Tomcat via JMX in the Tomcat Users' Guide. Rather than repeating that information here (which is mostly about configuration, connection, etc.), please go read the official documentation.

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• Wiki Markup
  JMX Bean: {{Catalina:type=Manager,context=\[context name\],host=\[hostname\]}}

• Attributes: activeSessions
  

External Monitoring Tools

Plug-in-based monitoring software like Nagios and Icinga may need some help interacting with Tomcat's JMXProxyServlet. check_jmx is a Perl script that can be used with these tools to monitor Tomcat via the JMXProxyServlet.