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MoSKito, an open-source solution by Anotheria, is a multi-purpose, non-invasive, interval-based monitoring system kit that collects, stores and provides instant analysis of a Tomcat application’s performance and behavior data.
JavaMelody can monitor your JavaEE/Tomcat application from dev to production. It is open-source and easy: get the first view of your application in about 2 minutes from now.
Other plug-in-based monitoring software like Nagios or Icinga may need some help interacting with Tomcat's JMXProxyServlet. tools/check_jmxproxy.pl is a Perl script that can be used with these tools to monitor Tomcat via the JMXProxyServlet.
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