chrony is an implementation of Network Time Protocol

install

apt install chrony

sample config specify ntp server at server or ntp server pool for pool

$ grep -E -v "^#|^$" /etc/chrony/chrony.conf
server 192.168.xxx.xxx iburst minpoll 6 maxpoll 10
keyfile /etc/chrony/chrony.keys
driftfile /var/lib/chrony/chrony.drift
logdir /var/log/chrony
maxupdateskew 100.0
rtcsync
makestep 1 3

reload configuration

systemctl status chronyd
journalctl -u chrony -f
systemctl force-reload chrony

show system track performance

chronyc tracking

show current time sources

chronyc sources

show information about drift rate and offset estimation process

chronyc sourcestats

show the last valid measurement and other information

chronyc ntpdata

server

For server settings, at least add a allow line. cmdallow and bindcmdaddress lines are optional which is for monitoring access

$ grep -E -v "^#|^$" /etc/chrony/chrony.conf
server 192.168.xxx.xxx iburst minpoll 6 maxpoll 10
keyfile /etc/chrony/chrony.keys
driftfile /var/lib/chrony/chrony.drift
logdir /var/log/chrony
maxupdateskew 100.0
rtcsync
makestep 1 3
allow 192.168.xxx.0/24
cmdallow 192.168.xxx.0/24
bindcmdaddress 127.0.0.1
bindcmdaddress 192.168.xxx.xxx

show list of clients

chronyc clients

specify a remote host to which chronyd is to be connected (using udp/323) default is localhost

cronyc -h 192.168.xxx.xxx