apt install ntp
mkdir /var/log/ntpsec/
chown ntpsec:ntpsec /var/log/ntpsec
nano /etc/ntpsec/ntp.conf
driftfile /var/lib/ntpsec/ntp.drift
leapfile /usr/share/zoneinfo/leap-seconds.list
# To enable Network Time Security support as a server, obtain a certificate
# (e.g. with Let's Encrypt), configure the paths below, and uncomment:
# nts cert CERT_FILE
# nts key KEY_FILE
# nts enable
statsdir /var/log/ntpsec/
statistics loopstats peerstats clockstats
filegen loopstats file loopstats type day enable
filegen peerstats file peerstats type day enable
filegen clockstats file clockstats type day enable
tos maxclock 11
tos minclock 4 minsane 3
server ntp0.fau.de iburst
server ntp1.fau.de iburst
server ntp2.fau.de iburst
server ntp3.fau.de iburst
# By default, exchange time with everybody, but don't allow configuration.
restrict default kod nomodify nopeer noquery limited
# Local users may interrogate the ntp server more closely.
restrict 127.0.0.1
restrict ::1
systemctl restart ntpd
ntpq -p
remote refid st t when poll reach delay offset jitter
=======================================================================================================
ntp0.rrze.uni-erlangen.de .GPS. 1 u 28 64 1 18.8282 -1.4043 0.0000
ntp1.rrze.uni-erlangen.de .DCFp. 1 u 27 64 1 17.6352 -0.6459 0.0000
ntp2.rrze.uni-erlangen.de .MBGh. 1 u 26 64 1 16.8099 -2.2543 0.0000
ntp3.rrze.uni-erlangen.de .PZFs. 1 u 25 64 1 14.7981 -2.0840 0.0000
nano /etc/dhcp/dhcpd.conf
option ntp-servers 192.168.1.1;
apt install sntp
nano /etc/dhcp/dhcpd6.conf
option dhcp6.sntp-servers 1234:1234:1234:1234::1;
systemctl restart isc-dhcp-server