class Aws::Rails::Middleware::ElasticBeanstalkSQSD

def build_default_docker_ips
  default_gw_ips = ['172.17.0.1']
  if File.exist?('/proc/net/route')
    File.open('/proc/net/route').each_line do |line|
      fields = line.strip.split
      next if fields.size != 11
      # Destination == 0.0.0.0 and Flags & RTF_GATEWAY != 0
      next unless fields[1] == '00000000' && fields[3].hex.anybits?(0x2)
      default_gw_ips << IPAddr.new_ntoh([fields[2].hex].pack('L')).to_s
    end
  end
  default_gw_ips
end