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How to set up timing if NTP was block by ISP?

+3 votes
1,332 views

How to set up timing if NTP was block by ISP? I have try many way such as link the timezone , getting from the hardware clock. However, it is not the solution.

Please advice.

posted Jan 15, 2014 by Tarun Singhal

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Your ISP doesn't have their own timeserver you can access??

I've never heard of an ISP blocking ntp protocol, unless they are  blocking /everything/ but web and email via proxy, whereupon they aren't  really an internet service provider, they are just a web-n-mail service  provider.
commented Jan 15, 2014 by Mandeep Sehgal

1 Answer

+1 vote

You can setup a your own NTP server following this howto:
http://brainwreckedtech.wordpress.com/2008/08/25/howto-run-your-own-ntp-server-when-your-isp-blocks-ports/ and adapting it for your machine, or you can use a workaround like trying to setup a cron job to run ntpdate every 15 minutes to sync system time with ntp.org public servers using unprivilleged port.

15 * * * * /usr/sbin/ntpdate -s -u -B pool.ntp.org

-s option tells ntpdate to print output to syslog; -u tells it to use unprivilleged port; -B tell it to adjust the time incrementally as oppose to instantly.

Then setup ntpd as a local ntp server for internal use. This ntpd uses it's localtime as the source instead of syncing from another ntp.org public server.

answer Jan 15, 2014 by Satish Mishra
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