diff --git a/db_transfer.py b/db_transfer.py
index 3c567db..f725435 100644
--- a/db_transfer.py
+++ b/db_transfer.py
@@ -189,6 +189,7 @@ class TransferBase(object):
 		socket.setdefaulttimeout(timeout)
 		last_rows = []
 		db_instance = obj()
+		ServerPool.get_instance()
 		import resource
 		logging.info('current process RLIMIT_NOFILE resource: soft %d hard %d'  % resource.getrlimit(resource.RLIMIT_NOFILE))
 		try: