With the arrival of OpenSSL 1.1.1, an upgraded Unbound, and some changes to the setup and init scripts, FreeBSD 12.0, currently in beta, now supports DNS over TLS out of the box.
DNS over TLS is just what it sounds like: DNS over TCP, but wrapped in a TLS session. It encrypts your requests and the server’s replies, and optionally allows you to verify the identity of the server. The advantages are protection against eavesdropping and manipulation of your DNS traffic; the drawbacks are a slight performance degradation and potential firewall traversal issues, as it runs over a non-standard port (TCP port 853) which may be blocked on some networks. Let’s take a look at how to set it up.