diff --git a/apps/emqx_dashboard/src/emqx_dashboard_listener.erl b/apps/emqx_dashboard/src/emqx_dashboard_listener.erl
index 5d5062948..6c4b84433 100644
--- a/apps/emqx_dashboard/src/emqx_dashboard_listener.erl
+++ b/apps/emqx_dashboard/src/emqx_dashboard_listener.erl
@@ -24,6 +24,7 @@
 -export([add_handler/0, remove_handler/0]).
 -export([pre_config_update/3, post_config_update/5]).
 -export([regenerate_minirest_dispatch/0]).
+-export([delay_job/1]).
 
 -behaviour(gen_server).
 
@@ -68,7 +69,7 @@ handle_call(_Request, _From, State) ->
 handle_cast(_Request, State) ->
     {noreply, State, hibernate}.
 
-handle_info(i18n_lang_changed, _State) ->
+handle_info(regenerate, _State) ->
     NewState = regenerate_minirest_dispatch(),
     {noreply, NewState, hibernate};
 handle_info({update_listeners, OldListeners, NewListeners}, _State) ->
@@ -146,7 +147,7 @@ remove_sensitive_data(Conf0) ->
     end.
 
 post_config_update(_, {change_i18n_lang, _}, _NewConf, _OldConf, _AppEnvs) ->
-    delay_job(i18n_lang_changed);
+    delay_job(regenerate);
 post_config_update(_, _Req, NewConf, OldConf, _AppEnvs) ->
     OldHttp = get_listener(http, OldConf),
     OldHttps = get_listener(https, OldConf),
diff --git a/apps/emqx_prometheus/src/emqx_prometheus_api.erl b/apps/emqx_prometheus/src/emqx_prometheus_api.erl
index b08cd8388..44e0fac16 100644
--- a/apps/emqx_prometheus/src/emqx_prometheus_api.erl
+++ b/apps/emqx_prometheus/src/emqx_prometheus_api.erl
@@ -50,15 +50,15 @@ schema("/prometheus") ->
                 description => ?DESC(get_prom_conf_info),
                 tags => ?TAGS,
                 responses =>
-                    #{200 => prometheus_setting_schema()}
+                    #{200 => prometheus_setting_response()}
             },
         put =>
             #{
                 description => ?DESC(update_prom_conf_info),
                 tags => ?TAGS,
-                'requestBody' => prometheus_setting_schema(),
+                'requestBody' => prometheus_setting_request(),
                 responses =>
-                    #{200 => prometheus_setting_schema()}
+                    #{200 => prometheus_setting_response()}
             }
     };
 schema("/prometheus/stats") ->
@@ -84,7 +84,13 @@ security() ->
 %%--------------------------------------------------------------------
 
 setting(get, _Params) ->
-    {200, emqx:get_raw_config([<<"prometheus">>], #{})};
+    Raw = emqx:get_raw_config([<<"prometheus">>], #{}),
+    Conf =
+        case emqx_prometheus_schema:is_recommend_type(Raw) of
+            true -> Raw;
+            false -> emqx_prometheus_config:to_recommend_type(Raw)
+        end,
+    {200, Conf};
 setting(put, #{body := Body}) ->
     case emqx_prometheus_config:update(Body) of
         {ok, NewConfig} ->
@@ -112,7 +118,7 @@ stats(get, #{headers := Headers}) ->
 %% Internal funcs
 %%--------------------------------------------------------------------
 
-prometheus_setting_schema() ->
+prometheus_setting_request() ->
     [{prometheus, #{type := Setting}}] = emqx_prometheus_schema:roots(),
     emqx_dashboard_swagger:schema_with_examples(
         Setting,
@@ -122,6 +128,14 @@ prometheus_setting_schema() ->
         ]
     ).
 
+%% Always return recommend setting
+prometheus_setting_response() ->
+    {_, #{value := Example}} = recommend_setting_example(),
+    emqx_dashboard_swagger:schema_with_example(
+        ?R_REF(emqx_prometheus_schema, recommend_setting),
+        Example
+    ).
+
 legacy_setting_example() ->
     Summary = <<"legacy_deprecated_setting">>,
     {Summary, #{
diff --git a/apps/emqx_prometheus/src/emqx_prometheus_config.erl b/apps/emqx_prometheus/src/emqx_prometheus_config.erl
index 66d53f2db..a24b52537 100644
--- a/apps/emqx_prometheus/src/emqx_prometheus_config.erl
+++ b/apps/emqx_prometheus/src/emqx_prometheus_config.erl
@@ -23,6 +23,7 @@
 -export([pre_config_update/3, post_config_update/5]).
 -export([update/1]).
 -export([conf/0, is_push_gateway_server_enabled/1]).
+-export([to_recommend_type/1]).
 
 update(Config) ->
     case
@@ -60,7 +61,8 @@ pre_config_update(?PROMETHEUS, MergeConf, OriginConf) ->
 to_recommend_type(Conf) ->
     #{
         <<"push_gateway">> => to_push_gateway(Conf),
-        <<"collectors">> => to_collectors(Conf)
+        <<"collectors">> => to_collectors(Conf),
+        <<"enable_basic_auth">> => false
     }.
 
 to_push_gateway(Conf) ->
@@ -123,7 +125,7 @@ update_push_gateway(Prometheus) ->
     end.
 
 update_auth(#{enable_basic_auth := New}, #{enable_basic_auth := Old}) when New =/= Old ->
-    emqx_dashboard_listener:regenerate_minirest_dispatch(),
+    emqx_dashboard_listener:delay_job(regenerate),
     ok;
 update_auth(_, _) ->
     ok.
diff --git a/apps/emqx_prometheus/test/emqx_prometheus_SUITE.erl b/apps/emqx_prometheus/test/emqx_prometheus_SUITE.erl
index c50813938..496919b10 100644
--- a/apps/emqx_prometheus/test/emqx_prometheus_SUITE.erl
+++ b/apps/emqx_prometheus/test/emqx_prometheus_SUITE.erl
@@ -78,7 +78,7 @@ groups() ->
     ].
 
 suite() ->
-    [{timetrap, {seconds, 30}}].
+    [{timetrap, {seconds, 60}}].
 
 common_tests() ->
     emqx_common_test_helpers:all(?MODULE).
diff --git a/apps/emqx_prometheus/test/emqx_prometheus_api_SUITE.erl b/apps/emqx_prometheus/test/emqx_prometheus_api_SUITE.erl
index ad2b3d5ec..cc20e60c7 100644
--- a/apps/emqx_prometheus/test/emqx_prometheus_api_SUITE.erl
+++ b/apps/emqx_prometheus/test/emqx_prometheus_api_SUITE.erl
@@ -80,29 +80,42 @@ set_special_configs(_App, _) ->
 %%--------------------------------------------------------------------
 %% Cases
 %%--------------------------------------------------------------------
+%% we return recommend config for prometheus even if prometheus is legacy.
 t_legacy_prometheus_api(_) ->
     Path = emqx_mgmt_api_test_util:api_path(["prometheus"]),
     Auth = emqx_mgmt_api_test_util:auth_header_(),
     {ok, Response} = emqx_mgmt_api_test_util:request_api(get, Path, "", Auth),
 
+    OldConf = emqx:get_raw_config([prometheus]),
     Conf = emqx_utils_json:decode(Response, [return_maps]),
+    %% Always return new config.
     ?assertMatch(
         #{
-            <<"push_gateway_server">> := _,
-            <<"interval">> := _,
-            <<"enable">> := _,
-            <<"vm_statistics_collector">> := _,
-            <<"vm_system_info_collector">> := _,
-            <<"vm_memory_collector">> := _,
-            <<"vm_msacc_collector">> := _,
-            <<"headers">> := _
+            <<"collectors">> :=
+                #{
+                    <<"mnesia">> := <<"disabled">>,
+                    <<"vm_dist">> := <<"disabled">>,
+                    <<"vm_memory">> := <<"disabled">>,
+                    <<"vm_msacc">> := <<"disabled">>,
+                    <<"vm_statistics">> := <<"disabled">>,
+                    <<"vm_system_info">> := <<"disabled">>
+                },
+            <<"enable_basic_auth">> := false,
+            <<"push_gateway">> :=
+                #{
+                    <<"enable">> := true,
+                    <<"headers">> := #{<<"Authorization">> := <<"some-authz-tokens">>},
+                    <<"interval">> := <<"1s">>,
+                    <<"job_name">> := <<"${name}~${host}">>,
+                    <<"url">> := <<"http://127.0.0.1:9091">>
+                }
         },
         Conf
     ),
-    #{<<"enable">> := Enable} = Conf,
+    #{<<"push_gateway">> := #{<<"enable">> := Enable}} = Conf,
     ?assertEqual(Enable, undefined =/= erlang:whereis(emqx_prometheus)),
 
-    NewConf = Conf#{
+    NewConf = OldConf#{
         <<"interval">> => <<"2s">>,
         <<"vm_statistics_collector">> => <<"enabled">>,
         <<"headers">> => #{
@@ -113,7 +126,7 @@ t_legacy_prometheus_api(_) ->
     {ok, Response2} = emqx_mgmt_api_test_util:request_api(put, Path, "", Auth, NewConf),
 
     Conf2 = emqx_utils_json:decode(Response2, [return_maps]),
-    ?assertMatch(NewConf, Conf2),
+    ?assertEqual(NewConf, Conf2),
 
     EnvCollectors = application:get_env(prometheus, collectors, []),
     PromCollectors = prometheus_registry:collectors(default),
@@ -153,11 +166,11 @@ t_legacy_prometheus_api(_) ->
         emqx_config:get([prometheus])
     ),
 
-    NewConf1 = Conf#{<<"enable">> => (not Enable)},
+    NewConf1 = OldConf#{<<"enable">> => (not Enable)},
     {ok, _Response3} = emqx_mgmt_api_test_util:request_api(put, Path, "", Auth, NewConf1),
     ?assertEqual((not Enable), undefined =/= erlang:whereis(emqx_prometheus)),
 
-    ConfWithoutScheme = Conf#{<<"push_gateway_server">> => "127.0.0.1:8081"},
+    ConfWithoutScheme = OldConf#{<<"push_gateway_server">> => "127.0.0.1:8081"},
     ?assertMatch(
         {error, {"HTTP/1.1", 400, _}},
         emqx_mgmt_api_test_util:request_api(put, Path, "", Auth, ConfWithoutScheme)
@@ -267,8 +280,7 @@ t_stats_no_auth_api(_) ->
     %% undefined is legacy prometheus
     case emqx:get_config([prometheus, enable_basic_auth], undefined) of
         true ->
-            {ok, _} = emqx:update_config([prometheus, enable_basic_auth], false),
-            emqx_dashboard_listener:regenerate_minirest_dispatch();
+            {ok, _} = emqx:update_config([prometheus, enable_basic_auth], false);
         _ ->
             ok
     end,
@@ -278,6 +290,7 @@ t_stats_no_auth_api(_) ->
 
 t_stats_auth_api(_) ->
     {ok, _} = emqx:update_config([prometheus, enable_basic_auth], true),
+    emqx_dashboard_listener:regenerate_minirest_dispatch(),
     Auth = emqx_mgmt_api_test_util:auth_header_(),
     JsonAuth = [{"accept", "application/json"}, Auth],
     request_stats(JsonAuth, Auth),