# File lib/facter/util/macaddress.rb, line 11
    def self.macaddress
      iface = default_interface
      Facter.warn "Could not find a default route. Using first non-loopback interface" if iface.empty?

      macaddress = `#{ifconfig_command} #{iface} | /usr/bin/awk '/ether/{print $2;exit}'`.chomp
      macaddress.empty? ? nil : macaddress
    end