diff --git a/shadowsocks/server.py b/shadowsocks/server.py
index c18ad1c..0815389 100755
--- a/shadowsocks/server.py
+++ b/shadowsocks/server.py
@@ -25,6 +25,7 @@ import signal
 
 if __name__ == '__main__':
     import inspect
+
     file_path = os.path.dirname(os.path.realpath(inspect.getfile(inspect.currentframe())))
     sys.path.insert(0, os.path.join(file_path, '../'))
 
@@ -43,7 +44,8 @@ def main():
 
     try:
         import resource
-        logging.info('current process RLIMIT_NOFILE resource: soft %d hard %d'  % resource.getrlimit(resource.RLIMIT_NOFILE))
+        logging.info(
+            'current process RLIMIT_NOFILE resource: soft %d hard %d' % resource.getrlimit(resource.RLIMIT_NOFILE))
     except ImportError:
         pass
 
@@ -68,7 +70,7 @@ def main():
 
     tcp_servers = []
     udp_servers = []
-    dns_resolver = asyncdns.DNSResolver()
+    dns_resolver = asyncdns.DNSResolver(config['black_hostname_list'])
     if int(config['workers']) > 1:
         stat_counter_dict = None
     else:
@@ -103,10 +105,11 @@ def main():
         a_config = config.copy()
         ipv6_ok = False
         logging.info("server start with protocol[%s] password [%s] method [%s] obfs [%s] obfs_param [%s]" %
-                (protocol, password, method, obfs, obfs_param))
+                     (protocol, password, method, obfs, obfs_param))
         if 'server_ipv6' in a_config:
             try:
-                if len(a_config['server_ipv6']) > 2 and a_config['server_ipv6'][0] == "[" and a_config['server_ipv6'][-1] == "]":
+                if len(a_config['server_ipv6']) > 2 and a_config['server_ipv6'][0] == "[" and a_config['server_ipv6'][
+                    -1] == "]":
                     a_config['server_ipv6'] = a_config['server_ipv6'][1:-1]
                 a_config['server_port'] = int(port)
                 a_config['password'] = password
@@ -151,11 +154,13 @@ def main():
             logging.warn('received SIGQUIT, doing graceful shutting down..')
             list(map(lambda s: s.close(next_tick=True),
                      tcp_servers + udp_servers))
+
         signal.signal(getattr(signal, 'SIGQUIT', signal.SIGTERM),
                       child_handler)
 
         def int_handler(signum, _):
             sys.exit(1)
+
         signal.signal(signal.SIGINT, int_handler)
 
         try:
@@ -191,6 +196,7 @@ def main():
                         except OSError:  # child may already exited
                             pass
                     sys.exit()
+
                 signal.signal(signal.SIGTERM, handler)
                 signal.signal(signal.SIGQUIT, handler)
                 signal.signal(signal.SIGINT, handler)