[arch-general] LXC Containers

I'm trying to setup my first LXC containers. I've managed to bootstrap an Arch container, but can't login to it even after manually adding a password to root in it's shadow file. I've also tried using /usr/lib/lxc/templates/lxc-ubuntu to setup an Ubuntu container. That seems to always return E: Invalid Release file, no entry for main/binary-x86_64/Packages no matter which release I try. Does anyone happen to know how to solve one or both of these problems? Thanks, =-Jameson