[3950] Expained behavior of the server when "kea_verbose" is used.

doc/guide/keactrl.xml

@@ -118,7 +118,13 @@ kea_verbose=no
         The <parameter>kea_verbose</parameter> parameter specifies the verbosity
         of the servers being started. When <parameter>kea_verbose</parameter>
         is set to "yes" the logging level of the server is set to DEBUG.
-        Otherwise, the default logging level is used.
+        Modification of the logging severity in a configuration file, as
+        described in <xref linkend="logging"/>, will have no effect as long
+        as the <parameter>kea_verbose</parameter> is set to "yes". Setting
+        it to "no" will cause the server to use the logging levels specified
+        in the Kea configuration file for respective loggers. If no
+        logging configuration is specified, the default settings will be
+        used.
       </para>
 
       <note>

doc/guide/logging.xml

@@ -450,6 +450,19 @@
 
         </para>
 
+        <note>
+          <para>
+            The keactrl tool, described in <xref linkend="keactrl"/>, can be
+            configured to start the servers in the verbose mode. If this is
+            the case, the settings of the logging severity in the configuration
+            file will have no effect, i.e. the servers will use logging severity
+            of DEBUG regardless of the logging settings specified in the configuration
+            file. If you need to control severity via configuration file, please
+            make sure that the <parameter>kea_verbose</parameter> value is set to
+            "no" within the keactrl configuration.
+          </para>
+        </note>
+
         </section>
 
         <section>