mkdir WEB-INF

cd WEB-INF

touch web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

  xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee

           http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"

  version="3.1" metadata-complete="true">

  <display-name>Router for Tomcat</display-name>

  <error-page>

    <error-code></error-code>

    <location>/index.html</location>

  </error-page>

</web-app>