As you are deploying OpenBSD, consider Absolute OpenBSD, by Michael W. Lucas. I rave about the book, and have done so for years, so I won't do it again here. Except to shill it: A sample chapter is available for download from the publisher, NoStarch Press:
https://www.nostarch.com/download/samples/ao2e_ch8.pdf and the book is available in several formats. Discount from the author here:
https://www.michaelwlucas.com/nonfic...solute-openbsd