Network Time Protocol (NTP) automatically syncs your system’s time with a remote server. With the NTP server, you can keep your system time up to date as per the main server. Your system clock time may drift slightly from the time you have set on the clock, but the up-to-date time on the system helps you to find the logs from the time and date you want to check.
1. Following are the steps to install and configure NTP Server on Centos.
# sudo yum install ntp
2. Once the installation is complete, you can run this command to run the service on boot time -
# service enable ntpd
3. You can start/s top or restart the NTP service with the command given below –
# service ntpd start
# service ntpd stop
# service ntpd restart
4. After installation of the NTP server, you can click on this link –https://www.pool.ntp.org/en/ for the NTP Public Pool time server. Then, select the continent where your server is located and find your country on the NTP server list.
5. Now, edit the /etc/ntp.conf configuration file of the NTP daemon and comment on the default public server from pool.ntp.org, and change the list provided by your country.
# sever 0.centos.pool.ntp.org iburst
# sever 1.centos.pool.ntp.org iburst
Change it to
sever 0.ro.pool.ntp.org iburst
sever 1.ro.pool.ntp.org iburst
6. If you want to allow customers from your networks to sync time with this server, then make changes in the NTP configuration such as given below –
restrict 192.168.1.0 netmask 255.255.255.0 nomodify notrap
7. As per the nomodify notrap, your clients don’t have permission to configure the server. However, you can add a rule in the firewall if it is enabled on your server.
# firewall-cmd –add-service=ntp –permanent
8. Reload the firewall.
# firewall-cmd –reload
9. Start and enable the NTP server
# systemctl start ntpd
# systemctl enable ntpd
10. Check the NTP status to ensure it is running fine.
# systemctl status ntpd
11. You can verify the time sync by executing this command below –
# ntpq -p
# date –R