Automatically start your containers
To automatically start your containers at boot, all you have to do is to put symlinks to your containers config files in the/etc/lxc/auto/ directory. For example for your previously created container (it’s important that your symlink has the same name as your container):
sudo ln -s /var/lib/lxc/myfirstcontainer/config /etc/lxc/auto/myfirstcontainer