Re: [libvirt-users] libvirt_lxc namespace and umount in global namespace

On Thu, Feb 20, 2014 at 01:47:52PM +0100, Olivier Nicaise wrote: > Hi, > > I am currently having an issue with the libvirt_lxc binary that is launched > when starting a lxc instance using libvirt. This process seems to have its > own namespace for mounts. > What happens is that if I umount something in the global namespace, it > stays mounted in the libvirt_lxc namespace. > I'm working with drbd, and after unmounting the mount point, I want to > change the state of the drbd resource as Secondary. But if fails. Indeed, > libvirt_lxc has still the resource which is mounted in its namespace. > > > Currently, I wanted to test the setns tool to enter the namespace and > umount the mount point. But I am currently on Ubuntu 12.04 with a 3.2.0-59 > kernel which does not have /proc/[pid]/ns/mnt > I can't upgrade to 3.8 (which have the proc mnt file) as the drbd tools are > not compatible. > > Do you have an idea of what I could try ? Ahh, interesting scenario that I'd not considered. With LXC there are in fact 3 mounts namespaces in play - The host OS namespace - The libvirt_lxc namespace - The actual container namespace The libvirt_lxc namespace is basically the same as the host namespace, but with the addition of a devpts for the container's /dev/pts. We explicitly don't allow dynamic changes to propagate from the host OS to the container namespace, however, it sounds like we *should* allow host OS changes to propagage to the libvirt_lxc process namespace. Can you file a bug about this, so it doesn't get forgotten. Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/:| |: http://libvirt.org -o- http://virt-manager.org:| |: http://autobuild.org -o- http://search.cpan.org/~danberr/:| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc:|