How to Enable CGI Mode in Apache Tomcat

Hello Coders, I hope you are all doing well.

Today, I had to enable the CGI mode in Tomcat, while facing lots of issue in the same. So, I thought that, after successful deployment, I would write an article in the same simplified steps. Here it is!

• First, download the Apache Tomcat (choose the version that is compatible with your application; in my case, I am using the latest one).
• Go to the CATALINA_HOME/conf and modify the following files:
  • web.xml (Here, we will enable the CGI support in Tomcat)
    • To enable CGI support in Tomcat, we have to uncomment servlet and servlet-mapping of CGI servlet in web.xml.
    • After uncommenting the servlet and servlet-mapping of CGI, we have to add one param value in that servlet mapping to execute our CGI.
  • context.xml
    • We have to set the attribute "privileged" to true for Context.

<!-- web.xml -->

<servlet>
  <servlet-name>cgi</servlet-name>
  <servlet-class>org.apache.catalina.servlets.CGIServlet</servlet-class>
  <init-param>
    <param-name>executable</param-name>
    <param-value></param-value>
  </init-param>
  <init-param>
    <param-name>cgiPathPrefix</param-name>
    <param-value>WEB-INF/cgi</param-value>
  </init-param>
  <load-on-startup>5</load-on-startup>
</servlet>

<servlet-mapping>
	<servlet-name>cgi</servlet-name>
	<url-pattern>/cgi-bin/*</url-pattern>
</servlet-mapping>

<!-- context.xml -->

<Context privileged="true">
</Context>

• Go to the CATALINA_HOME/webapps/ROOT/  directory.
  • Check weather WEB-INF  directory is exist or not, if not create the directory  WEB-INF .
  • Create another directory named as cgi under  WEB-INF.
• Now, your Tomcat is CGI enabled. You can copy any CGI file under this directory, and it will run successfully.
• Your base URL will be <<request protocol>>>://<<server-ip>>:<<server-port>>/cgi-bin/<<name of cgi>>, in my case i.e. http://localhost:8080/cgi-bin/test.cgi
• For more understanding, you can look for CGI-howto section in Tomcat

Let me know if you face any issue after this deployment. Happy Coding!