Configure NTP on ESX
December 12th, 2007 | 
Author: Keeping consistent date and time between your ESX hosts is critical. You can set up NTP sync manually by following the instructions from VMware, or you can run a script to configure ESX automatically.
I first found out about the setup_ntp.sh script from VMware Support. I have since discovered VMColonel » Script to setup NTP on ESX 3.x. I’m guessing this is where the script originated from? Regardless, this script has been a tremendous time saver.
Here’s a high level overview of how to use the script:
- Download (extract it from the .zip) the script and transfer it to the /tmp directory on your ESX host(s)
- From a console session (I usually do it remote with Putty) enter the following:
- #cd /tmp
- #./setup_ntp.sh
- The script prompts you to enter the ntp servers you want to sync with. Enter them one at a time. The script walks you through entering as many as you want and asks you if you want to enter another ntp server or not.
- I usually use pool ntp.org servers – us.pool.ntp.org and pool.ntp.org to be exact.
- The script configures all files and saves backups of the originals and opens the ESX firewall.
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Where is the script?
Kevin,
I updated the link in step 1.
If the link still does not work then click the Files Page link just under the header at the top of the site.
Rich, you may want to consider using the country-specific servers when configuring NTP, i.e., using 0.us.pool.ntp.org instead of just pool.ntp.org. This ensures that you get an NTP server closer to you. More information is available here:
http://www.pool.ntp.org/
Thanks!
Rich,
I have found using 0.vmware.pool.ntp.org as a good external NTP refernece for my ESX hosts. I have a similiar post on the subject @
http://www.ipmer.com/2008/04/enabling-ntp-on-esx-servers.html
Take Care.
Carlo.