I’ve gotten really spoiled recently (say, for the last two years) on setting NTP on ESX servers. I found a nifty script that would take an answer file, do all the necessary firewall and startup tweaking and that was that.
Unfortunately, it only worked if I used a certain version of winscp and my Dell 620. For whatever reason, any other combination broke the script (confirmed by other admins here). Well, the 620 died a couple months ago, just after my cube migration. I didn’t bother fixing the script because recent (as in published in 2008 or newer) versions of ESX added NTP configuration to the GUI and that has worked fine.
Now, I am installing 3.02 again and NTP configuration looks like this:
(1) update /etc/ntp.conf
restrict default kod nomodify notrap
(2) update /etc/ntp/step-tickers
(3) update /etc/hosts (if using hostname)
(4) using putty or similar to goto the console, login as root and run the following command. This opens the appropriate ports and enables the NTP daemon to talk with the external server.
root@esxhost# esxcfg-firewall –enableService ntpClient
(5) Restart the NTP service.
root@esxhost# service ntpd restart
(7) Now you can set the local hardware clock to the NTP synchronized local system time. Run:
root@esxhost# hwclock –systohc
Sheesh. Props to the VMware Forums for coughing up that bit of goodness.