Change warning to warn on logs

The LEVEL field will contain one of the following values: INFO, WARN, ERROR, FATAL or DEBUG. Normally, similar kind of log events are group by the same log level. The following table describes the different levels:

--Level	Description

INFO	 The INFO level designates informational messages that highlight the progress of the application at coarse-grained level. This log entries must not affect the process performance. For example, the process reports a user has successfully logged on.
WARN	 The WARN level designates potentially harmful situations. There is a minor problem that should be fixed. For instance, a file has reached a predefined size.
ERROR	 The ERROR level designates error events that might still allow the application to continue running. There is a problem that affects process performance. For instance, timeout occurred when trying to get some information.
FATAL	 The FATAL level designates very severe error events that will presumably lead the application to abort. Process cannot longer work. For instance, a SIGKILL has been issued.
DEBUG	 The DEBUG Level designates fine-grained informational events that are most useful to debug an application. It provides a high verbose level. It should used in productions environments only when a problem requires some kind of workaround.