Configuring the NTP Daemon

Install NTPD

sudo yum install ntp

Check NTPD Configuration

Check the server lines in /etc/ntp.conf. Modern config setups sometimes delegate the server lists to:

/etc/ntp/ntpservers:

clock.redhat.com
clock2.redhat.com

/etc/ntp/step-tickers:

clock.redhat.com
clock2.redhat.com

If you are acting as a master for other clients on your network you will need to uncomment the following line and modify the network address in /etc/ntp.conf:

# Hosts on local network are less restricted.
restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap

Restart NTPD

sudo service ntpd restart

It is a good idea to tail /var/log/messages and make sure the ntpd started happily.

Verify NTPD Peering

sudo ntpq -p

Verify NTPD Synchronization

You will need to wait 20 minutes after restarting the ntpd before this command will display the proper results:

sudo ntptrace

Enable Service on Restart

sudo chkconfig ntpd on