How To Prevent FreeBSD's Base ntpd(8) From Binding To All Interfaces
Particularly useful with jail hosts
For quite some time I have been using openntpd instead of FreeBSD's base ntpd(8), exclusively because of the latter's tendency to bind to all available interfaces and addresses, and its former inability to be configured in a way that it binds to specific IP address. Hhowever, it appears that from FreeBSD 11.1 onwards we can specify ntpd's listen IP address(es). The following article explains how to bind FreeBSD's base ntpd to single IPv4 address, and IPv4 loopback address.