Restricting NTP access
Here’s what I use in /etc/ntp.conf
. The restrict
lines below originated from Ubuntu. The iburst
and maxpoll 9
settings are necessary in FreeBSD to avoid ntpd
switching between PLL and FLL modes every now and then.
server your-server1 iburst maxpoll 9 server your-server2 iburst maxpoll 9 server your-server3 iburst maxpoll 9 server 127.127.1.0 fudge 127.127.1.0 stratum 10 restrict -4 default kod nomodify nopeer noquery notrap restrict -6 default kod nomodify nopeer noquery notrap restrict your-server1 nomodify nopeer noquery notrap restrict your-server2 nomodify nopeer noquery notrap restrict your-server3 nomodify nopeer noquery notrap restrict -4 127.0.0.1 restrict -6 ::1 restrict 127.127.1.0 logconfig =clockall +peerall +sysall +syncall