diff --git a/src/server.py b/src/server.py
--- a/src/server.py
+++ b/src/server.py
@@ -33,11 +33,17 @@ class Miniserver:
 		self._ss.listen(1)
 
 	def serve(self):
-		while True:
-			with Connection(self._ss,self._ssl) as c:
-				p=multiprocessing.Process(target=Server.run,args=(c,self._filename,self._treeFile))
+		p=None
+		with self._ss:
+			while True:
+				connection=Connection(self._ss,self._ssl)
+				if p and p.is_alive():
+					with connection as c:
+						c[0].readMsg()
+						c[1].writeMsg({"command":"deny"})
+					continue
+				p=multiprocessing.Process(target=Server.run,args=(connection,self._filename,self._treeFile))
 				p.start()
-				p.join()
 
 
 class Server(NetNode):
@@ -51,9 +57,10 @@ class Server(NetNode):
 		self._dataFileHandle=None
 
 	@staticmethod
-	def run(*args):
-		s=Server(*args)
-		s.serve()
+	def run(connection,*args):
+		with connection as c:
+			s=Server(c,*args)
+			s.serve()
 
 	@property
 	def _dataFile(self):
@@ -75,6 +82,8 @@ class Server(NetNode):
 				self._outcoming.writeMsg({"command":"deny"})
 			if jsonData["action"]=="pull" and self.isLocked():
 				self._outcoming.writeMsg({"command":"deny"})
+			if jsonData["action"]=="push" and not self.isLocked():
+				self._lock()
 
 			self._outcoming.writeMsg({"command":"init", "version":conf.version})