Robert, If your NTP server will be on 7/24, I would uninstall chrony and install ntpd which is still included in CentOS 7. Configure as usual.
For the differences between chrony and ntpd reference: http://thegeekdiary.com/centos-rhel-7-chrony-vs-ntp-differences-between-ntpd...
Essentially, chrony is more for laptops with intermittant network connections, and ntpd is better suited to always-on servers