Iowa Code § 580.6: Service of notice.

Said notice shall be served as follows:

1. By posting a duplicate copy for ten days prior to the day of sale in three public places in the township in which the sale is to take place, and

2. If the owner of the progeny resides in the said county, by also serving a duplicate copy on the owner in the manner in which original notices are served, at least ten days prior to the day of sale.