Monitoring the JVM is an important part of administering the Apache Tomcat server. The Tomcat manager provides a quick way to check our server's status by displaying how many HTTP threads are active, the storage allocation in the various memory pools plus other helpful data.
To learn how to check the status of the Apache Tomcat Server, follow these 6 steps:
http://localhost:8080/manager/htmland submit that address to the browser.
tomcat-users.xml(make sure to provide the correct spelling and case):