Configuration of NTP is an often overlooked step in setting up a VMware ESX environment. It is important to keep accurate time not only on the guests but also on the hosts. In the 3.5 release of ESX you can configure NTP from the VI Client, but some older releases require configuration from the Service Console. Here are the steps involved in NTP configuration from the Service Console.
My steps below assume the usage of the nano text editor however you could certainly choose a different text editor. For help with using nano see the nano Command Manual or this quick Introduction.
Modify the NTP config file:
Contents of ntp.conf should look like:
restrict default kod nomodify notrap
Modify the NTP Step Tickers config file:
Contents of step-tickers should look like:
Enable NTP in the firewall
esxcfg-firewall --enableService ntpClient
Restart the NTP service
service ntpd restart
Set the NTP service to start automatically at system startup
chkconfig ntpd on