sudo apt-get install chrony

sudo nano /etc/chrony/chrony.conf

pool time.google.com       iburst minpoll 2 maxpoll 2 maxsources 3 maxdelay 0.3
pool time.facebook.com     iburst minpoll 2 maxpoll 2 maxsources 3 maxdelay 0.3
pool time.euro.apple.com   iburst minpoll 2 maxpoll 2 maxsources 3 maxdelay 0.3
pool time.apple.com        iburst minpoll 2 maxpoll 2 maxsources 3 maxdelay 0.3
pool ntp.ubuntu.com        iburst minpoll 2 maxpoll 2 maxsources 3 maxdelay 0.3
​
# This directive specify the location of the file containing ID/key pairs for
# NTP authentication.
keyfile /etc/chrony/chrony.keys
​
# This directive specify the file into which chronyd will store the rate
# information.
driftfile /var/lib/chrony/chrony.drift
​
# Uncomment the following line to turn logging on.
#log tracking measurements statistics
​
# Log files location.
logdir /var/log/chrony
​
# Stop bad estimates upsetting machine clock.
maxupdateskew 5.0
​
# This directive enables kernel synchronisation (every 11 minutes) of the
# real-time clock. Note that it can’t be used along with the 'rtcfile' directive.
rtcsync
​
# Step the system clock instead of slewing it if the adjustment is larger than
# one second, but only in the first three clock updates.
makestep 0.1 -1
​
# Get TAI-UTC offset and leap seconds from the system tz database
leapsectz right/UTC
​
# Serve time even if not synchronized to a time source.
local stratum 10

sudo systemctl restart chronyd.service

chronyc sources

chronyc tracking