diff --git a/openhtf/plugs/__init__.py b/openhtf/plugs/__init__.py
index <HASH>..<HASH> 100644
--- a/openhtf/plugs/__init__.py
+++ b/openhtf/plugs/__init__.py
@@ -516,6 +516,7 @@ class PlugManager(object):
     if self._xmlrpc_server:
       _LOG.debug('Shutting down Plug XMLRPC Server.')
       self._xmlrpc_server.shutdown()
+      self._xmlrpc_server.server_close()
       self._xmlrpc_server = None
 
     _LOG.debug('Tearing down all plugs.')
Also close the underlying socket for the plug manager's xmlrpc server