diff --git a/o_manager.py b/o_manager.py
index 1bc26e2..58312ba 100644
--- a/o_manager.py
+++ b/o_manager.py
@@ -84,6 +84,23 @@ class OManager:
         instance["weight"] = 0
         self.reset_lb()
 
+    def remove_op(self, idx):
+        instance = self.get_instance(idx)
+        if not instance:
+            return
+        instance["op"].stop()
+        instance["weight"] = 0
+        self.instances.remove(instance)
+        self.reset_lb()
+
+    def remove_all_op(self):
+        for instance in self.instances:
+            instance["op"].stop()
+            instance["weight"] = 0
+        self.instances = []
+        self.new_idx = 0
+        self.reset_lb()
+
     def start_all(self):
         for instance in self.instances:
             instance["op"].start()
@@ -132,6 +149,7 @@ class OManager:
             ping_stat = i["op"].get_ping_stat(lines=max(n_up, n_down))
             ping_stat = [i.split(",")[-1] != "-1" for i in ping_stat]
             #print("ping status:", ping_stat)
+
             def all_equal(n, status):
                 for j in range(min(n, len(ping_stat))):
                     if ping_stat[-(j+1)] != status:
@@ -140,10 +158,10 @@ class OManager:
             # all up
             if all_equal(n_up, True):
                 i["weight"] = 1
-                #print("all_up")
+                # print("all_up")
             if all_equal(n_down, False):
                 i["weight"] = 0
-                #print("all_down")
+                # print("all_down")
             weights.append(i["weight"])
         return weights
 
@@ -163,7 +181,7 @@ class OManager:
                     os.kill(self.PID, signal.SIGUSR1)
                 except:
                     print("error applying weights")
-            #else:
+            # else:
                 #print("weight not changed, weights:", new_weights)
 
     async def run_cmd(self, cmd):
diff --git a/test.py b/test.py
index b831b97..000dae6 100644
--- a/test.py
+++ b/test.py
@@ -73,7 +73,7 @@ class StartInstatnceHandler(tornado.web.RequestHandler):
             self.write("start all")
 
 
-class StopAll(tornado.web.RequestHandler):
+class StopInstatnceHandler(tornado.web.RequestHandler):
     def get(self):
         idx = self.get_query_argument("i", None)
         if idx != None:
@@ -84,13 +84,25 @@ class StopAll(tornado.web.RequestHandler):
             self.write("stop all")
 
 
+class RemoveInstatnceHandler(tornado.web.RequestHandler):
+    def get(self):
+        idx = self.get_query_argument("i", None)
+        if idx != None:
+            om.remove_op(int(idx))
+            self.write("remove sucess!")
+        else:
+            om.remove_all_op()
+            self.write("remove all")
+
+
 def make_app():
     return tornado.web.Application([
         (r"/", MainHandler),
         (r"/select", ConfigsHandeler),
         (r"/create", CreateInstantceHandler),
         (r"/start", StartInstatnceHandler),
-        (r"/stop", StopAll)
+        (r"/stop", StopInstatnceHandler),
+        (r"/remove", RemoveInstatnceHandler),
     ])