[lxc-devel] Shutting down containers properly

[Christian Seiler]

Hi,

> Have you looked at the lxc-shutdown script we have in Ubuntu and the
> integration we have with upstart?

No, not yet, but I'll look at it later.

> lxc-shutdown sends two different signals:
>  reboot => SIGINT
>  shutdown => SIGPWR
>
> These are caught by upstart and will trigger a clean reboot or 
> shutdown
> of the container. It's what happens on shutdown of the host in 12.04 
> LTS.

On a Debian container I had lying around here it had no effect 
whatsoever, because there's nothing in the /etc/inittab catching it.

Is it document behaviour that upstart shuts down on SIGPWR? (upstart 
has no /etc/inittab where this may be configured, right?) Because if it 
is that easy to cause upstart deterministically to shut down, then that 
is definitely something we should use.

Still, I think my initial rationale still holds that lxc-stop should 
shut down by default, because I certainly didn't expect lxc-stop to kill 
everything with SIGKILL when I tried it for the first time. So basically 
all I'm saying is that Ubuntu's lxc-shutdown logic should be implemented 
in lxc-stop and that it should be a bit more generic with the 
possibility that the user can configure different methods in the config 
file.

Regards,
Christian