diff --git a/class/core/ssh_terminal.py b/class/core/ssh_terminal.py
index 733289b8e..b7fcb3409 100644
--- a/class/core/ssh_terminal.py
+++ b/class/core/ssh_terminal.py
@@ -28,7 +28,7 @@ import paramiko
 from flask_socketio import SocketIO, emit, send
 
 
-class ssh_terminal:
+class ssh_terminal(object):
 
     __debug_file = 'logs/terminal.log'
     __log_type = 'SSH终端'
@@ -59,6 +59,14 @@ class ssh_terminal:
         ht = threading.Thread(target=self.heartbeat)
         ht.start()
 
+    @classmethod
+    def instance(cls, *args, **kwargs):
+        if not hasattr(ssh_terminal, "_instance"):
+            with ssh_terminal._instance_lock:
+                if not hasattr(ssh_terminal, "_instance"):
+                    ssh_terminal._instance = ssh_terminal(*args, **kwargs)
+        return ssh_terminal._instance
+
     def debug(self, msg):
         msg = "{} - {}:{} => {} \n".format(mw.formatDate(),
                                            self.__host, self.__port, msg)
diff --git a/route/__init__.py b/route/__init__.py
index cd9855dff..fe41dca6a 100755
--- a/route/__init__.py
+++ b/route/__init__.py
@@ -596,8 +596,6 @@ def index(reqClass=None, reqAction=None, reqData=None):
 
 ##################### ssh  start ###########################
 shell = None
-shell_client = None
-
 
 @socketio.on('webssh_websocketio')
 def webssh_websocketio(data):
@@ -605,11 +603,8 @@ def webssh_websocketio(data):
         emit('server_response', {'data': '会话丢失，请重新登陆面板!\r\n'})
         return
 
-    global shell_client
-    if not shell_client:
-        import ssh_terminal
-        shell_client = ssh_terminal.ssh_terminal()
-
+    import ssh_terminal
+    shell_client = ssh_terminal.instance()
     shell_client.run(request.sid, data)
     return