Iowa Code § 655A.7: Proof and record of service.

If the terms and conditions as to which there is default are not performed within the thirty days, the party serving the notice or causing it to be served shall file for record in the office of the county recorder a copy of the notice with proofs of service required under section 655A.4 attached or endorsed on it and, in case of service by publication, a personal affidavit that personal service could not be made within this state, and when those documents are filed and recorded, the record is constructive notice to all parties of the due foreclosure of the mortgage.