[ntp:security] issue with pool.ntp.org

Brad Knowles knowles at ntp.org
Tue Jun 17 15:52:53 UTC 2008

Damian H wrote:

> We've reduced the period of synch to 12 hours in lot of our servers and they
> are not being blocked but in the blocked ones this is not being solved. Is
> there something we can make to unblock all our servers?

We don't maintain the pool.ntp.org servers.  Everything in that subdomain is 
managed by Ask Bjørn Hansen, and you can read more about that at 

I suspect your problem is that you've gotten latched onto a single NTP 
server that is not functioning well, but you'll have to go through the 
debugging process with him.

That said, you would be protected from these problems if you weren't using 
ntpdate, but instead had a proper NTP server infrastructure defined.  We try 
to cover all the appropriate information in the Community Supported 
Documentation at <http://support.ntp.org/>, but you might want to pay 
special attention our "Getting Started" page at 

Brad Knowles <knowles at ntp.org>
Postmaster, Listmaster, & PGP Keymaster

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