Configuring a NTP server can be a great help for your local network. Debian comes with a built in package called ntpsec and confiruing it is relatively straight forward.
To install the package run the following command:
sudo apt update && sudo apt install ntpsec -y
Next copy the configuration file so you have an original backup:
sudo cp /etc/ntpsec/ntp.conf /etc/ntpsec/ntp.original
Now edit the ntp.conf file:
sudo vi /etc/ntpsec/ntp.conf
edit the file commenting out ntp settings and add the swiss pool (for me since I am in Switzerland, you can of course pick your own, you can find an overview here of available public ntp servers: https://www.ntppool.org/en/)
# pool 0.debian.pool.ntp.org iburst # pool 1.debian.pool.ntp.org iburst # pool 2.debian.pool.ntp.org iburst pool ch.pool.ntp.org iburst
and
restrict 10.0.0.0/8 # Allow campus access restrict 192.168.0.0/16 # Allow WLAN access restrict ch.pool.ntp.org # Allow access
Write the file and exit
Run the following to enable the NTP service and start it:
sudo systemctl enable ntpsec sudo systemctl start ntpsec
To check that everything is working you can use the following commands:
timedatectl
which after around 5 minutes gives you an output like this (before 5 minutes the System clock synchronized may show “no”):
or
ntpq -c sysinfo
That shows you the NTP server you are connected to, what Stratum (delay) you have:
