The writ must be directed to the sheriff of any county in which property of the defendant may be and require the sheriff to attach and keep safely all the money or property of the defendant described in the order for attachment within the county not exempt from execution, or so much thereof as is sufficient to satisfy the amount demanded by the writ of attachment, whichever is less, unless the defendant gives the sheriff security by the undertaking of at least two sufficient sureties in an amount equal to the amount demanded by the writ or the value of the property levied upon, whichever is less, apart from costs, in lawful money of the United States, in which case the writ must require the sheriff to take such an undertaking.