Take the 2-minute tour ×
Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free, no registration required.

Can I use NTP service through proxy? how to do it? I want NTP auto sync my clock through proxy.

share|improve this question
    
What kind of proxy? –  Martin Schröder Oct 15 '12 at 6:26

3 Answers 3

NTP uses UDP packets with port number 123. So if you are behind aproxy or firewall, and the proxy or firewall blocks the UDP port 123, the public NTP servers you specify in /etc/ntp.conf won't be reachable to your host. If you can't reach them then you need to use internal ntp servers if they are available on your network.

share|improve this answer

You can use NTP servers setup in your network DMZ or setup to also have direct access to the Internet. This way that NTP server can synchronize time via NTP servers on the Internet but also provide a time source to your internal servers.

share|improve this answer

If internal NTP servers (with their own clock source; e.g. GPS) and dual-homed NTP servers are not an option, then a lower accuracy option is htpdate (Note: not ntpdate). This pulls time from the timestamp inside a HTTP header - so it is not the most accurate.

Note: this system presumes that the web servers used as a time source have accurate time

See http://www.clevervest.com/htp/

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.