diff --git a/apps/iot/src/iot_logger.erl b/apps/iot/src/iot_logger.erl
index feed296..79ff5bd 100644
--- a/apps/iot/src/iot_logger.erl
+++ b/apps/iot/src/iot_logger.erl
@@ -21,7 +21,6 @@
 -define(LOG_FILE, "north_data").
 
 -record(state, {
-    root_dir :: string(),
     file_path :: string(),
     file
 }).
@@ -49,19 +48,11 @@ start_link() ->
     {ok, State :: #state{}} | {ok, State :: #state{}, timeout() | hibernate} |
     {stop, Reason :: term()} | ignore).
 init([]) ->
-    RealFile = make_file(),
-    RootDir =  code:root_dir() ++ "/log/",
-    FilePath = RootDir ++ RealFile,
-    lager:debug("root_dir: ~p", [FilePath]),
-    case filelib:is_dir(RootDir) of
-        false ->
-            file:make_dir(RootDir);
-        true ->
-            ok
-    end,
+    ensure_dir(),
+    FilePath = make_file(),
     {ok, File} = file:open(FilePath, [append, binary]),
 
-    {ok, #state{file = File, root_dir = RootDir, file_path = FilePath}}.
+    {ok, #state{file = File, file_path = FilePath}}.
 
 %% @private
 %% @doc Handling call messages
@@ -82,9 +73,9 @@ handle_call(_Request, _From, State = #state{}) ->
     {noreply, NewState :: #state{}} |
     {noreply, NewState :: #state{}, timeout() | hibernate} |
     {stop, Reason :: term(), NewState :: #state{}}).
-handle_cast({write, Data}, State = #state{root_dir = RootDir, file_path = OldFilePath, file = OldFile}) ->
+handle_cast({write, Data}, State = #state{file_path = OldFilePath, file = OldFile}) ->
     Line = format(Data),
-    FilePath = RootDir ++ make_file(),
+    FilePath = make_file(),
     case FilePath =:= OldFilePath of
         true ->
             ok = file:write(OldFile, Line),
@@ -143,4 +134,14 @@ time_prefix() ->
 make_file() ->
     {Year, Month, Day} = erlang:date(),
     Prefix = io_lib:format("~b~2..0b~2..0b-", [Year, Month, Day]),
-    lists:flatten(Prefix ++ ?LOG_FILE).
\ No newline at end of file
+    RootDir = code:root_dir() ++ "/log/",
+    lists:flatten(RootDir ++ Prefix ++ ?LOG_FILE).
+
+ensure_dir() ->
+    RootDir = code:root_dir() ++ "/log/",
+    case filelib:is_dir(RootDir) of
+        true ->
+            ok;
+        false ->
+            file:make_dir(RootDir)
+    end.
\ No newline at end of file
diff --git a/apps/iot/src/iot_sup.erl b/apps/iot/src/iot_sup.erl
index bd20919..93b395e 100644
--- a/apps/iot/src/iot_sup.erl
+++ b/apps/iot/src/iot_sup.erl
@@ -28,6 +28,15 @@ start_link() ->
 init([]) ->
     SupFlags = #{strategy => one_for_one, intensity => 1000, period => 3600},
     Specs = [
+        #{
+            id => 'iot_logger',
+            start => {'iot_logger', start_link, []},
+            restart => permanent,
+            shutdown => 2000,
+            type => worker,
+            modules => ['iot_logger']
+        }
+
         #{
             id => 'iot_endpoint_sup',
             start => {'iot_endpoint_sup', start_link, []},
@@ -54,6 +63,7 @@ init([]) ->
             type => supervisor,
             modules => ['iot_host_sup']
         }
+
     ],
 
     {ok, {SupFlags,  pools() ++ Specs}}.