[ntp:questions] NTP servers not accessible on some networks

Jochen Bern Jochen.Bern at LINworks.de
Sun May 18 12:59:47 UTC 2014

On -10.01.-28163 20:59, Antonio Marcheselli wrote:
> I've got some servers which have stopped synchronising on the configured
> NTP server. [...] I thought the NTP server had gone down, but
> then found that in another country I could still sync to the same NTP
> server.
> [...] Any chance some ISPs are blocking some NTP servers or maybe
> port 123 on such servers??

GeoIP blocking (google that) today is an established technology to
protect your publicly-reachable networks, especially if the services
offered aren't meant or even illegal (copyrights) to be offered to the
entire planet. Chances are that access to the NTP servers are a
collateral of a central firewall having had such a feature activated -
not that that'ld help you any ...

								J. Bern
*NEU* - NEC IT-Infrastruktur-Produkte im <http://www.linworks-shop.de/>:
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Jochen Bern, Systemingenieur --- LINworks GmbH <http://www.LINworks.de/>
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