From fd4292b6ce98a64e1df0eb173e21f4ff0e80d5a6 2013-12-29 18:34:50
From: Min RK <benjaminrk@gmail.com>
Date: 2013-12-29 18:34:50
Subject: [PATCH] Merge pull request #4720 from minrk/ssh-no-mux

never use ssh multiplexer in tunnels

`ssh -f` is [broken in OpenSSH](https://bugzilla.mindrot.org/show_bug.cgi?id=1948) when a ControlMaster multiplexed connection is used.

`-S none` disables the multiplexed connection.

closes #4717
---

diff --git a/IPython/external/ssh/tunnel.py b/IPython/external/ssh/tunnel.py
index 6aa3f2d..0cf9bcb 100644
--- a/IPython/external/ssh/tunnel.py
+++ b/IPython/external/ssh/tunnel.py
@@ -214,7 +214,7 @@ def openssh_tunnel(lport, rport, server, remoteip='127.0.0.1', keyfile=None, pas
         server, port = server.split(':')
         ssh += " -p %s" % port
         
-    cmd = "%s -f -L 127.0.0.1:%i:%s:%i %s sleep %i" % (
+    cmd = "%s -f -S none -L 127.0.0.1:%i:%s:%i %s sleep %i" % (
         ssh, lport, remoteip, rport, server, timeout)
     tunnel = pexpect.spawn(cmd)
     failed = False