Tomcat: Unauthorized error (401) while accessing tomcat.

Apache Tomcat, often referred to as Tomcat Server, is an open-source Java Servlet Container developed by the Apache Software Foundation (ASF). Tomcat implements several Java EE specifications including Java Servlet, JavaServer Pages (JSP), Java EL, and WebSocket, and provides a "pure Java" HTTP web server environment in which Java code can run.

After installing tomcat, while running http://localhost:8080 , you may come across this error "401 Unauthorized error while accessing tomcat.". To solve this issue we need to do the following steps.



Answer:
 1. Edit the tomcat users file  " vi /etc/tomcat/tomcat-users.xml"
 2. Then Change the Permission for the user your are getting Error.

 The HTML interface is protected against CSRF but the text and JMX interfaces are not. To maintain the CSRF protection: Users with the manager-gui role should not be granted either the manager-script or manager-jmx roles.