From mboxrd@z Thu Jan 1 00:00:00 1970 From: Serge Hallyn Subject: uevent when moving nic between network namespaces? Date: Thu, 11 Oct 2012 22:13:28 -0500 Message-ID: <20121012031328.GA5472@sergelap> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org, Dan Kegel , =?iso-8859-1?Q?St=E9phane?= Graber , lxc-users-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Daniel Lezcano , containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: containers.vger.kernel.org Hi, Dan Kegel (cc:d) found an interesting nuisance relating to upstart and network interfaces with lxc containers. In particular, when you start a container, two veths are created. A uevent for their creation is sent, and so a 'network-interface' upstart job is created for each. One of the veths is passed into the container. When the container shuts down, the veth in the init-net-ns gets a net-device-removed uevent, so the network-interface upstart job goes away. But the veth in the container doesn't cause a net-device-removed upstart uevent to be sent. So its network-interface upstart job sticks around. The details are at: https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1065589 I notice that when simply renaming a netdev (sudo ip link set veth1 name veth2) then udevadm monitor shows: KERNEL[17945.234850] move /devices/virtual/net/veth2 (net) UDEV [17945.235758] move /devices/virtual/net/veth2 (net) but when I do 'sudo ip link set veth2 netns 27689' then 'udevadm monitor' shows nothing. When I do sudo ip link set veth1 netns 32296 (in process 32296) sudo ip link set veth1 name veth2 then, again udevadm monitor shows nothing. So the question is, should the kernel be sending uevents for net-device-removed and then net-device-added when a nic is moved between network namespaces? Or should lxc just fake that? -serge