Tomcat is an open-source web server and servlet container developed by the Apache Software Foundation, it was initially known as Jakarta Tomcat or Tomcat. If you have a website running on a production server with a Tomcat environment, your website might get thousands of web requests per minute. At this point, you most likely feel that the memory resources usage in one Tomcat JVM become overwhelmed. To prevent your server from going down or unresponsive, you can configure a Tomcat cluster by placing two or more Tomcat servers.