The Network Time Protocol daemon (ntpd) program is a Linux operating system daemon. It sets and maintains the system time of day in synchronism with time servers (Mills).
You need to configure ntpd via /etc/ntp.conf configuration file. The file is well documented and you easily configure it.
If ntpd is not installed use any one of the following command to install ntpd:
# yum install ntpOR
# up2date ntp
You should at least set following parameter in /etc/ntp.conf config file:
server <Time Server Name or IP Address>
For example, open /etc/ntp.conf file using vi text editor:
# vi /etc/ntp.conf
Locate server parameter and set it as follows:
Save the file and restart the ntpd service:
# /etc/init.d/ntpd start
You can synchronize the system clock to an NTP server immediately with following command:
# ntpdate pool.ntp.org
5 May 14:36:01 ntpdate: adjust time server 18.104.22.168 offset -0.343242 sec