diff --git a/src/ejabberd_config.erl b/src/ejabberd_config.erl
index a31651430..ca4b427d4 100644
--- a/src/ejabberd_config.erl
+++ b/src/ejabberd_config.erl
@@ -34,7 +34,7 @@
 	 prepare_opt_val/4, transform_options/1, collect_options/1,
 	 convert_to_yaml/1, convert_to_yaml/2, v_db/2,
 	 env_binary_to_list/2, opt_type/1, may_hide_data/1,
-	 is_elixir_enabled/0, v_dbs/1, v_dbs_mods/1,
+	 is_elixir_enabled/0, v_dbs/1, v_dbs_mods/1, v_host/1, v_hosts/1,
 	 default_db/1, default_db/2, default_ram_db/1, default_ram_db/2,
 	 default_queue_type/1, queue_dir/0, fsm_limit_opts/1,
 	 use_cache/1, cache_size/1, cache_missed/1, cache_life_time/1,
@@ -971,6 +971,33 @@ v_dbs_mods(Mod) ->
 				       (atom_to_binary(M, utf8))/binary>>, utf8)
 	      end, v_dbs(Mod)).
 
+-spec v_host(binary()) -> binary().
+v_host(Host) ->
+    hd(v_hosts([Host])).
+
+-spec v_hosts([binary()]) -> [binary()].
+v_hosts(Hosts) ->
+    ServerHosts = get_myhosts(),
+    lists:foldr(
+      fun(Host, Acc) ->
+	      case lists:member(Host, ServerHosts) of
+		  true ->
+		      ?ERROR_MSG("Failed to reuse route ~s because it's "
+				 "already registered on a virtual host",
+				 [Host]),
+		      erlang:error(badarg);
+		  false ->
+		      case lists:member(Host, Acc) of
+			  true ->
+			      ?ERROR_MSG("Host ~s is defined multiple times",
+					 [Host]),
+			      erlang:error(badarg);
+			  false ->
+			      [Host|Acc]
+		      end
+	      end
+      end, [], Hosts).
+
 -spec default_db(module()) -> atom().
 default_db(Module) ->
     default_db(global, Module).
diff --git a/src/mod_echo.erl b/src/mod_echo.erl
index a218c5f40..26cf60611 100644
--- a/src/mod_echo.erl
+++ b/src/mod_echo.erl
@@ -60,9 +60,8 @@ reload(Host, NewOpts, OldOpts) ->
 depends(_Host, _Opts) ->
     [].
 
-mod_opt_type(host) -> fun iolist_to_binary/1;
-mod_opt_type(hosts) ->
-    fun(L) -> lists:map(fun iolist_to_binary/1, L) end.
+mod_opt_type(host) -> fun ejabberd_config:v_host/1;
+mod_opt_type(hosts) -> fun ejabberd_config:v_hosts/1.
 
 mod_options(_Host) ->
     [{host, <<"echo.@HOST@">>}, {hosts, []}].
diff --git a/src/mod_http_upload.erl b/src/mod_http_upload.erl
index 846071a2a..afba0f09a 100644
--- a/src/mod_http_upload.erl
+++ b/src/mod_http_upload.erl
@@ -151,9 +151,9 @@ stop(ServerHost) ->
 
 -spec mod_opt_type(atom()) -> fun((term()) -> term()) | [atom()].
 mod_opt_type(host) ->
-    fun iolist_to_binary/1;
+    fun ejabberd_config:v_host/1;
 mod_opt_type(hosts) ->
-    fun (L) -> lists:map(fun iolist_to_binary/1, L) end;
+    fun ejabberd_config:v_hosts/1;
 mod_opt_type(name) ->
     fun iolist_to_binary/1;
 mod_opt_type(access) ->
diff --git a/src/mod_mix.erl b/src/mod_mix.erl
index 51464e63f..78e5d0251 100644
--- a/src/mod_mix.erl
+++ b/src/mod_mix.erl
@@ -315,9 +315,8 @@ is_not_subscribed({error, StanzaError}) ->
 depends(_Host, _Opts) ->
     [{mod_pubsub, hard}].
 
-mod_opt_type(host) -> fun iolist_to_binary/1;
-mod_opt_type(hosts) ->
-    fun (L) -> lists:map(fun iolist_to_binary/1, L) end.
+mod_opt_type(host) -> fun ejabberd_config:v_host/1;
+mod_opt_type(hosts) -> fun ejabberd_config:v_hosts/1.
 
 mod_options(_Host) ->
     [{host, <<"mix.@HOST@">>},
diff --git a/src/mod_muc.erl b/src/mod_muc.erl
index d7bb194c1..8a7fd1664 100644
--- a/src/mod_muc.erl
+++ b/src/mod_muc.erl
@@ -889,10 +889,9 @@ mod_opt_type(db_type) -> fun(T) -> ejabberd_config:v_db(?MODULE, T) end;
 mod_opt_type(ram_db_type) -> fun(T) -> ejabberd_config:v_db(?MODULE, T) end;
 mod_opt_type(history_size) ->
     fun (I) when is_integer(I), I >= 0 -> I end;
-mod_opt_type(host) -> fun iolist_to_binary/1;
+mod_opt_type(host) -> fun ejabberd_config:v_host/1;
 mod_opt_type(name) -> fun iolist_to_binary/1;
-mod_opt_type(hosts) ->
-    fun (L) -> lists:map(fun iolist_to_binary/1, L) end;
+mod_opt_type(hosts) -> fun ejabberd_config:v_hosts/1;
 mod_opt_type(max_room_desc) ->
     fun (infinity) -> infinity;
 	(I) when is_integer(I), I > 0 -> I
diff --git a/src/mod_multicast.erl b/src/mod_multicast.erl
index ea6e5b442..632c3d271 100644
--- a/src/mod_multicast.erl
+++ b/src/mod_multicast.erl
@@ -1083,9 +1083,8 @@ depends(_Host, _Opts) ->
 
 mod_opt_type(access) ->
     fun acl:access_rules_validator/1;
-mod_opt_type(host) -> fun iolist_to_binary/1;
-mod_opt_type(hosts) ->
-    fun(L) -> lists:map(fun iolist_to_binary/1, L) end;
+mod_opt_type(host) -> fun ejabberd_config:v_host/1;
+mod_opt_type(hosts) -> fun ejabberd_config:v_hosts/1;
 mod_opt_type(name) -> fun iolist_to_binary/1;
 mod_opt_type({limits, Type}) when (Type == local) or (Type == remote) ->
     fun(L) ->
diff --git a/src/mod_proxy65.erl b/src/mod_proxy65.erl
index 5a348a819..cc3546cf2 100644
--- a/src/mod_proxy65.erl
+++ b/src/mod_proxy65.erl
@@ -113,9 +113,8 @@ depends(_Host, _Opts) ->
     [].
 
 mod_opt_type(access) -> fun acl:access_rules_validator/1;
-mod_opt_type(host) -> fun iolist_to_binary/1;
-mod_opt_type(hosts) ->
-    fun(L) -> lists:map(fun iolist_to_binary/1, L) end;
+mod_opt_type(host) -> fun ejabberd_config:v_host/1;
+mod_opt_type(hosts) -> fun ejabberd_config:v_hosts/1;
 mod_opt_type(hostname) ->
     fun(undefined) -> undefined;
        (H) -> iolist_to_binary(H)
diff --git a/src/mod_pubsub.erl b/src/mod_pubsub.erl
index 8ca4c6564..d96933e11 100644
--- a/src/mod_pubsub.erl
+++ b/src/mod_pubsub.erl
@@ -3847,9 +3847,8 @@ purge_offline(Host, LJID, Node) ->
 mod_opt_type(access_createnode) -> fun acl:access_rules_validator/1;
 mod_opt_type(db_type) -> fun(T) -> ejabberd_config:v_db(?MODULE, T) end;
 mod_opt_type(name) -> fun iolist_to_binary/1;
-mod_opt_type(host) -> fun iolist_to_binary/1;
-mod_opt_type(hosts) ->
-    fun (L) -> lists:map(fun iolist_to_binary/1, L) end;
+mod_opt_type(host) -> fun ejabberd_config:v_host/1;
+mod_opt_type(hosts) -> fun ejabberd_config:v_hosts/1;
 mod_opt_type(ignore_pep_from_offline) ->
     fun (A) when is_boolean(A) -> A end;
 mod_opt_type(last_item_cache) ->
diff --git a/src/mod_vcard.erl b/src/mod_vcard.erl
index fe8af76f4..39da3472e 100644
--- a/src/mod_vcard.erl
+++ b/src/mod_vcard.erl
@@ -531,9 +531,8 @@ mod_opt_type(allow_return_all) ->
     fun (B) when is_boolean(B) -> B end;
 mod_opt_type(db_type) -> fun(T) -> ejabberd_config:v_db(?MODULE, T) end;
 mod_opt_type(name) -> fun iolist_to_binary/1;
-mod_opt_type(host) -> fun iolist_to_binary/1;
-mod_opt_type(hosts) ->
-    fun (L) -> lists:map(fun iolist_to_binary/1, L) end;
+mod_opt_type(host) -> fun ejabberd_config:v_host/1;
+mod_opt_type(hosts) -> fun ejabberd_config:v_hosts/1;
 mod_opt_type(matches) ->
     fun (infinity) -> infinity;
 	(I) when is_integer(I), I > 0 -> I