[tomcat] 403 Access Denied on Tomcat 8 Manager App without prompting for user/password

The solution that worked for me is edit context.xml files in both $CATALINA_HOME/webapps/manager/META-INF and $CATALINA_HOME/webapps/host-manager/META-INF where my ip is 123.123.123.123.

<Context antiResourceLocking="false" privileged="true" >
  <Valve className="org.apache.catalina.valves.RemoteAddrValve"
         allow="127\.\d+\.\d+\.\d+|::1|0:0:0:0:0:0:0:1|123.123.123.123" />
</Context>

I installed Tomcat 8.5 on Ubuntu and edited $CATALINA_HOME/conf/tomcat-users.xml:

<role rolename="admin-gui"/>
<role rolename="manager-gui"/>
<user username="myuser" password="mypass" roles="admin-gui,manager-gui"/>

However, I still couldn't access both Tomcat Web Application Manager (localhost:8080/manager/html) and Tomcat Virtual Host Manager (localhost:8080/host-manager/html) until I edited context.xml files.