[lxc-users] busybox template in ubuntu 14.04 fails to install /usr/sbin/init.lxc?

[Fajar A. Nugraha]

On Mon, May 12, 2014 at 1:25 AM, Dan Kegel <dank at kegel.com> wrote:
> This has probably been raised before, but unless you copy in init.lxc
> manually, e.g.
>
> sudo cp /usr/sbin/init.lxc /var/lib/lxc/busybox/rootfs/usr/sbin/
>
> the commands
>
> sudo lxc-create -n busybox -t busybox
> sudo lxc-execute -n busybox -- top
>
> will create the container, but fail on execute with the confusing message
>
> lxc-execute: Failed to find an lxc-init

My guess is that is intentional.

A busybox template (and probably the sshd template) should be as
simple and as small as possible, demonstrating the possible small
resource usage (in this case, disk space) of a container. So having it
able to start with lxc-start (and in the case of sshd, accepting
connections) is sufficient.

It is also not a straightforward matter to copy init.lxc. In ubuntu
trusty at least, I had to copy to other libraries manually to a ubuntu
container to make it work: liblxc.so.1 and libseccomp.so.2. For a
busybox container I imagine the dependencies will be much more.

An interesting note, however, is that on the said ubuntu container,
having /usr/sbin/init.lxc as a symlink for /bin/bash seem to work just
fine. Perhaps the same would work for busybox containers as well (in
this case, you might need a wrapper script instead of symlink)?

-- 
Fajar