Install NTPD Daemon to enable NTP in Linux
To enable NTP synchronisation over NTP (Network Time Protocol), all you need is to install NTP using yum command.
Main linux systems that understand following tutorial
Easy steps to install and configure NTP on CentOS
Login as the root user
Type the following command to install ntp
# yum install ntp
Turn on service
# chkconfig ntpd on
Synchronize the system clock with 0.pool.ntp.org server:
# ntpdate pool.ntp.org
Start the NTP:
# /etc/init.d/ntpd start
Configure crontab to use NTP on Linux Machine
Note: If you are using VPS (anything other than dedicated server), you will see following issue repeatedly. In such case, it is better to use ntpupdate with crontab utility instead of nptd service – which may fail to work sometimes.
Process of configuration
Stop the ntpd processes
# chkconfig ntpd off # /etc/init.d/ntpd stop
Create a shell script like this
>vi synctime #!/bin/bash /usr/sbin/ntpdate ntp.xs4all.nl
Add an entry in cron job
>crontab -e #min hour day_of_month month day_of_week user command */10 * * * * /home/work/scripts/crons/synctime > /dev/null 2>&1
It runs every ten minutes and you are done!