diff --git a/src/emqttd.erl b/src/emqttd.erl
index ee51546bc..4e9bd42d7 100644
--- a/src/emqttd.erl
+++ b/src/emqttd.erl
@@ -29,7 +29,7 @@
 -export([start/0, env/1, env/2,
          start_listeners/0, stop_listeners/0,
          load_all_mods/0, is_mod_enabled/1,
-         is_running/1]).
+         is_running/1, seed_now/0]).
 
 %% Utility functions.
 -export([reg_name/2]).
@@ -139,3 +139,12 @@ is_running(Node) ->
 reg_name(M, Id) when is_atom(M), is_integer(Id) ->
     list_to_atom(lists:concat([M, "_", Id])).
 
+seed_now() ->
+    case erlang:function_exported(erlang, timestamp, 0) of
+        true -> %% R18
+            random:seed(erlang:timestamp());
+        false ->
+            %% compress 'now()' warning...
+            random:seed(os:timestamp())
+    end.
+
diff --git a/src/emqttd_auth_username.erl b/src/emqttd_auth_username.erl
index 65586ae37..a923aee6d 100644
--- a/src/emqttd_auth_username.erl
+++ b/src/emqttd_auth_username.erl
@@ -142,8 +142,7 @@ md5_hash(SaltBin, Password) ->
     erlang:md5(<<SaltBin/binary, Password/binary>>).
 
 salt() ->
-    {A1,A2,A3} = now(),
-    random:seed(A1, A2, A3),
+    emqttd:seed_now(),
     Salt = random:uniform(16#ffffffff),
     <<Salt:32>>.
 
diff --git a/src/emqttd_broker.erl b/src/emqttd_broker.erl
index fc1b45912..8f90fa01f 100644
--- a/src/emqttd_broker.erl
+++ b/src/emqttd_broker.erl
@@ -218,7 +218,7 @@ stop_tick(TRef) ->
 %%%=============================================================================
 
 init([]) ->
-    random:seed(os:timestamp()),
+    emqttd:seed_now(),
     ets:new(?BROKER_TAB, [set, public, named_table]),
     % Create $SYS Topics
     emqttd_pubsub:create(topic, <<"$SYS/brokers">>),
diff --git a/src/emqttd_metrics.erl b/src/emqttd_metrics.erl
index aa62e9e71..0ef5bda1c 100644
--- a/src/emqttd_metrics.erl
+++ b/src/emqttd_metrics.erl
@@ -283,7 +283,7 @@ key(counter, Metric) ->
 %%%=============================================================================
 
 init([]) ->
-    random:seed(os:timestamp()),
+    emqttd:seed_now(),
     Metrics = ?SYSTOP_BYTES ++ ?SYSTOP_PACKETS ++ ?SYSTOP_MESSAGES,
     % Create metrics table
     ets:new(?METRIC_TAB, [set, public, named_table, {write_concurrency, true}]),
diff --git a/src/emqttd_stats.erl b/src/emqttd_stats.erl
index be15377dd..7a3f0be6f 100644
--- a/src/emqttd_stats.erl
+++ b/src/emqttd_stats.erl
@@ -143,7 +143,7 @@ setstats(Stat, MaxStat, Val) ->
 %%%=============================================================================
 
 init([]) ->
-    random:seed(os:timestamp()),
+    emqttd:seed_now(),
     ets:new(?STATS_TAB, [set, public, named_table, {write_concurrency, true}]),
     Topics = ?SYSTOP_CLIENTS ++ ?SYSTOP_SESSIONS ++ ?SYSTOP_PUBSUB ++ ?SYSTOP_RETAINED,
     ets:insert(?STATS_TAB, [{Topic, 0} || Topic <- Topics]),