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Tomcat Manager Configuration

This tutorial shows how to configure the tomcat manager application that can be used to administrate Tomcat. We will also show how to enable the default user and password and how to grant the roles required to run the manager application.
The Tomcat Manager is a very powerful tool for Tomcat administration. It allows you to use the following features:

  • Remote application deployment 
  • Cleanup of Idle session
  • Application undeployment and redeployment
  • Analysis of memory leaks
  • JVM status
  • Server status

The Tomcat Manager by default is disabled in Tomcat 7. In order to enable it, pickup the tomcat-users.xml in the conf folder of Tomcat 7. This file contains two users: tomcat and role1. These roles however are not enabled to use the manager gui, as you need an user with the "manager-gui" roles. So change the file so that it look like this:


<role rolename="manager-gui"/>
<user username="tomcat" password="s3cret" roles="manager-gui"/>

Logging into the Manager with the default username and password

So now with the above changes, you will be able to login into Tomcat Manager application with Tomcat manager-gui user name and password that is tomcat/s3cret.

Through this console, we can deploy new applications or modify the current application's state to stop, undeploy, start, reload, clear sessions, and so on as displayed by the following picture:

Checking Tomcat Status

One interesting feature of Tomcat Manager is the ability to inspect the the current status of the server by clicking on the Server Status, as shown in the following picture:

The server status UI will show the following details:

  • JVM status (Max memory, Total memory, Free memory)
  • Connection of AJP port 8009  (Connection state, Data sent, Data received, Client, Virtual host)
  • Connection on HTTP port 8080 (Connection state, Data sent, Data received, Client, Virtual host)
  • Server information (Tomcat version, OS version, JVM version, System architecture)


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