Unable to logon after several unsuccessful attempts
One answer
With the default tomcat setting, the user will be locked out for 300 seconds after 5 unsuccessful attempts. You need to wait for 300 seconds at least.
Reference: LockOut Realm http://tomcat.apache.org/tomcat-7.0-doc/config/realm.html#LockOut_Realm_-_org.apache.catalina.realm.LockOutRealm