Ohio Rev. Code § 2151.29
Service of summons, notices, and subpoenas, prescribed by section 2151.28 of the Revised Code, shall be made by delivering a copy to the person summoned, notified, or subpoenaed, or by leaving a copy at the person's usual place of residence. If the juvenile judge is satisfied that such service is impracticable, the juvenile judge may order service by registered or certified mail. If the person to be served is without the state but the person can be found or the person's address is known, or the person's whereabouts or address can with reasonable diligence be ascertained, service of the summons may be made by delivering a copy to the person personally or mailing a copy to the person by registered or certified mail.
Whenever it appears by affidavit that after reasonable effort the person to be served with summons cannot be found or the person's post-office address ascertained, whether the person is within or without a state, the clerk shall publish such summons once in a newspaper of general circulation throughout the county. The summons shall state the substance and the time and place of the hearing, which shall be held at least one week later than the date of the publication. A copy of the summons and the complaint, indictment, or information shall be sent by registered or certified mail to the last known address of the person summoned unless it is shown by affidavit that a reasonable effort has been made, without success, to obtain such address.
A copy of the advertisement, the summons, and the complaint, indictment, or information, accompanied by the certificate of the clerk that such publication has been made and that the summons and the complaint, indictment, or information have been mailed as required by this section, is sufficient evidence of publication and mailing. When a period of one week from the time of publication has elapsed, the juvenile court shall have full jurisdiction to deal with such child as provided by sections 2151.01 to 2151.99 of the Revised Code.
R.C. §2151.29