Add the realm parameter in the example config file

examples/etc/turnserver.conf

@@ -217,8 +217,15 @@
 #
 #oauth
 
+#The default realm to be used for the users when no explicit origin/realm 
+#relationship was found in the database. Must be used with long-term 
+#credentials mechanism or with TURN REST API.
+#
+#realm=realm
+
 # 'Static' user accounts for long term credentials mechanism, only.
 # This option cannot be used with TURN REST API.
+# This option require a realm.
 # 'Static' user accounts are NOT dynamically checked by the turnserver process, 
 # so that they can NOT be changed while the turnserver is running.
 #