Answer by Lester Cheung for Is it possible to start LXC container inside LXC container?

With Ubuntu 14.04 (trusty) you can simply add the following in the parent container config:

lxc.mount.auto = cgrouplxc.aa_profile = lxc-container-default-with-nesting

reference: https://ubuntu.com/server/docs/containers-lxc(search for "nesting)

Make sure that you have pre-configured network before booting to avoid an long pause before the login screen appears!

HTH