PSI Probe – Replacement for Tomcat Manager

PSI (Greek letter pronounced 'sai') Probe is an open source fork of Lambda Probe which has been inactive since 2006. PSI Probe does everything that Tomcat Manager does plus much, much more. 
Installation is as simple as adding the war file to the Tomcat webapps directory, adding roles to tomcat-users.xml, and then restarting the server. Installation details can be found here: . Probe is also compatible with the JBoss and WSO2 application servers.
Once installed and running probe is accessed using the URL similar to http://localhost:8080/probe. You will arrive at the home page with a list of applications and their current status. Click on the jasperserver-pro application and you will see the Summary page with a number of tabs on the right side of the page.
The sessions page shows all active sessions, click on a session and you will see details about the session, including the ability to kill a session.
Click on the Logs tab and you can examine a log and even tail one of the log files in real time.
The Treads tab lists all active threads and provides information about their state, plus how many times they have been in Waiting and Blocked state.
A very useful feature is the Memory utilization page under the System Information tab. Here you can monitor memory utilization in the various JVM memory spaces.
The Quick check tab provides a sanity check on the application server health with respect to running out of database connections, running out of memory, or losing access to resources on the file system. Quick check will:
  • Scan all available data sources and generate a maximum usage score for them.
  • Allocate one megabyte of memory into a byte array as an attempt to push the memory usage over the high watermark.
  • Create and then delete 10 files in a temporary directory.
Quick Check will report failure when:
  • At least one of the declared data sources is 100 percent used.
  • A memory allocation test (1 MB) generates an OutOfMemory exception.
  • A file-creation test encounters an IOException.

For a full list of features, FAQ, downloads and more go to