Section 232. Notice of nature of matrimonial action; proof of service

a. In
  an  action  to annul a marriage or for divorce or for separation, if the
  complaint is not personally served with the summons, the  summons  shall
  have  legibly written or printed upon the face thereof: "Action to annul
  a marriage", "Action to declare the nullity of a void marriage", "Action
  for a divorce", or "Action for a separation", as the case  may  be,  and
  shall  specify  the  nature of any ancillary relief demanded. A judgment
  shall not be rendered in favor of the  plaintiff  upon  the  defendant's
  default  in  appearing  or pleading, unless either (1) the summons and a
  copy of the complaint were personally delivered to the defendant; or (2)
  the copy of the summons (a) personally delivered to  the  defendant,  or
  (b) served on the defendant pursuant to an order directing the method of
  service  of  the  summons  in  accordance with the provisions of section
  three hundred eight or three hundred fifteen of the civil  practice  law
  and rules, shall contain such notice.
    b.   An   affidavit   or   certificate  proving  service  shall  state
  affirmatively in the body thereof that the required notice  was  written
  or  printed  on  the  face  of  the copy of the summons delivered to the
  defendant and what knowledge the affiant or  officer  who  executed  the
  certificate had that he was the defendant named and how he acquired such
  knowledge. The court may require the affiant or officer who executed the
  affidavit  or  certificate to appear in court and be examined in respect
  thereto.