# Working with the Jakarta NT Service

By Gal Shachor `<shachor@il.ibm.com>`

The Jakarta NT service is an executable that wraps the Tomcat servlet container and executes it in the background as an NT service. To install it you will need to:

1. Get a hold on the NT executable (jk_nt_service.exe)

- Download the executable from the win32/i386 directory found where you downloaded the Tomcat binary distribution. For those using Netscape as your browser, try downloading a zip version of the file, if available. There can be problems using Netscape to download DLL files.

2. Customize a properties file that provides the service with Tomcat information (wrapper.properties).

- Locate the wrapper.properties template file in your Tomcat conf directory.
- Update the wrapper.tomcat_home property to point at your tomcat home.
- Update the wrapper.java_home property to point at your Java home.

3. Install jk_nt_service by running it with the -i flag.

- Execute jk_nt_service -I <name of service> <path to updated wrapper properties>
- <name of service> should be a single word (without and spaces) such as Jakarta
- <path to updated wrapper properties> should point to your wrapper.properties file (and the service will check it's existence.)
- For example, a valid command line can be jk_nt_service -I Jakarta wrapper.properties

4. Start tomcat as a service.

- From the command line, execute net start <name of service> (e.g. net start Jakarta)
- From the NT services applet, highlight your service and press start.

Note: If the log file location in your wrapper.properties file points to the `logs` directory, and the `logs` directory doesn't yet exist, manually create it before starting the service.
5. Stop Tomcat as a service.

- From the command line, execute net stop <name of service> (e.g. net stop Jakarta)
- From the NT services applet, highlight your service and press stop.

Special note: The Tomcat service is using AJPV12 to perform clean shutdown and you should make sure that an AJPV12 connector is defined in your server.xml. In the absence of a configured AJPV12 port the Tomcat service will kill Tomcat abruptly (that is murder it) without giving it a chance to clean up.

Notice for JDK 1.3 users: There is a known problem in JDK 1.3 that affects Java applications being run as Windows NT services. The bug causes the service to terminate when the currently logged in user logs out. The simplest way to work around this problem is to use JDK 1.2. If your application requires JDK 1.3 features then you may want to look into javaserv or JavaService. Users have reported success with both of these packages but there may be others that work as well.

To remove the installed service, execute jk_nt_service -R <name of service>

# Advance Setup

1. Modify the Tomcat NT service properties. By default the service will run in manual mode and under the local system user account. To modify this, open the NT services applet, highlight your service and press startup. A popup window is opened and you will be able to customize the service to your satisfaction.
2. Modify the classpath. The classpath is determined by the wrapper.class_path properties, to modify it just add/remove/modify wrapper.class_path lines. The complete classpath is calculated by concatenating all the wrapper.class_path lines and putting ";" between them.
3. Execute several Tomcat instances. Say that you want one Tomcat to run for "production" and one for development, you can do that. All you will need to do is to install the Tomcat service twice and under two different names (and with different wrapper.properties file and server.xml files).

- Make sure that the AJPV12 and HTTP connectors are modified in each server.xml file to prevent a clash.
- Make sure to update the wrapper.shutdown_port property in wrapper.properties to point to the correct AJPV12 shutdown ports (default is 8007).

4. Modify the command line used to start Tomcat. The Tomcat service is taking all it's command line configuration from wrapper.properties! To customize the command line, edit the property wrapper.cmd_line and make sure that it makes a legal Java command line.

# Feedback

Please send feedback, bug report or any additional information to `<tomcat-user@jakarta.apache.org>`