# File lib/vagrant-lxc/action/create.rb, line 50
        def generate_container_name(env)
          container_name = "#{env[:root_path].basename}_#{env[:machine].name}"
          container_name.gsub!(/[^-a-z0-9_]/i, "")

          # milliseconds + random number suffix to allow for simultaneous
          # `vagrant up` of the same box in different dirs
          container_name << "_#{(Time.now.to_f * 1000.0).to_i}_#{rand(100000)}"

          # Trim container name to 64 chars, keeping "randomness"
          trim_point = container_name.size > 64 ? -64 : -(container_name.size)
          container_name[trim_point..-1]
        end