errors.rb

  DOWN_ERRORS = [
    Errno::ECONNRESET,
    Errno::EHOSTUNREACH,
    Errno::EINVAL,
    Errno::ECONNREFUSED,
    Errno::ENETUNREACH,
    Net::HTTPBadResponse,
    Net::HTTPHeaderSyntaxError,
    Net::ProtocolError,
    SocketError,
    Timeout::Error,
    EOFError,
  ]