Zorka is a powerful general purpose monitoring agent for your Java application servers. It is designed to integrate seamlessly your Java applications with popular monitoring systems.

Basic features (among others):

• integration with commonly used monitoring systems and protocols: Zabbix, Nagios, syslog, SNMP;

• programmability - zorka can be extended using Beanshell scripts;

• bytecode instrumentation - zorka features very configurable and powerful instrumentation engine that can be used to do virtually anything with collected values: aggregate statistics and present them in MBeans in various ways, send SNMP traps, syslog messages, zabbix traps, intercept object references and present them directly via JMX or use them in any way with Beanshell; instrumentation can be used for other tasks than basic monitoring (eg. audit trail);

• tracer - allows for recording method execution traces from you application; trace data is stored in local files and can be analyzed by simple viewer application; tracer integrates well with rest of instrumentation engine, giving lots of options of capturing various types of data and filtering information that is logged to trace files;

• performance metrics - very configurable metrics collector that offers sophiscated object tree traversal functionality and rich metric descriptions and preprocessing capabilities;

• mapped mbeans - user can map calculated values from anywhere into arbitrary mbean attributes; for example, you can fetch some collection (list) anywhere from your application and present its size() function as some mbean attribute; standard JMX clients can fetch these values (monitor presented collection length in our example);

Note that this is development snapshot of Zorka agent. While it works fairly well on author's production workloads, its configuration directives and BSH APIs are still changing and getting it to work might sometimes be a challenge (yet it works stable after being properly configured). In other works - it is still in flux: check download page often for new versions.

Interesting links:

• Introduction to Zorka

• Installation

• Configuration

• Zorka API Reference

• Changelog

• Downloads