[lxc-devel] [PATCH] Various fixes for Fedora/CentOS/OpenSUSE templates and systemd.

[Serge Hallyn]

Quoting Stéphane Graber (stgraber at ubuntu.com):
> On Wed, Oct 01, 2014 at 11:51:47AM -0400, Michael H. Warfield wrote:
> > On Wed, 2014-10-01 at 11:34 -0400, Stéphane Graber wrote:
> > 
> > [snip]
> > 
> > > > Would this be better if this paralleled autodev an we only disabled kmsg
> > > > by default if and when systemd was detected as the init system?  The
> > > > situation is very analogous to the autodev situation.  If a user were to
> > > > switch from say upstart to systemd and autodev is not specified in the
> > > > config, we default that to enabled when we detect systemd as the init
> > > > system at run time.  We could also default kmsg to 0 in the case of
> > > > systemd being the run time init system manager to prevent journald from
> > > > going into it's console message loop and burning CPU.  Would that work
> > > > better for you?  Since you can switch init systems from within the
> > > > container and may not have access to the container config file that's in
> > > > the host, something should be done to cover the run time case, like we
> > > > do with autodev.  That's what I was attempting to do...
> > 
> > > I'm not very much fond of having to do per-init system config changes
> > > but yeah, that sounds like a reasonable way to go.
> > 
> > > If we start getting more and more of those cases we may want to make
> > > things slightly more configurable by just having LXC include some
> > > default configuration files based on that detection.
> > 
> > Oh?  Sort of like conditional includes?  If lxc.init = systemd include
> > systemd.conf sort of thing?  It would have to be runtime conditional but
> > that does make some sense at that.
> 
> So I see a few ways of doing it:
>  0) We keep all the logic hardcoded as it is today for autodev.

Can we get a list of the things which need to be different?

AFAICS the lxc.autodev needs work, but once that work is done would be
fine for non-systemd hosts.

Currently, on an ubuntu system for unpriv users we have lxc.mount.entry
entries for basic devices which get bind-mounted from the host.  The
lxc.autodev case would simply be

1. create .local/share/lxc/container/rootfs.dev
2. at container start,
   a. bind-mount .local/share/lxc/container/rootfs.dev to
      .local/share/lxc/container/rootfs.dev/rootfs/dev
   b. for device in console full null random tty urandom zero; do
        bind mount /dev/$device .local/share/lxc/container/rootfs.dev/$device
	(creating the file if needed)

if lxc.autodev does this, is there any reason not to make autodev the
default?