NTP

[Shlomi Fish]

Hi all,


On Thu, May 1, 2014 at 9:45 PM, Geoff Shang <geoff at quitelikely.com> wrote:

> Hi,
>
> We have an array of devices and computers.  Two Linux machines, a win7
> box, an iMac, a Macbook Pro, an iPad, an iPad Mini, two iPods, three
> iPhones and two Nexus 7s.
>
> We have Internet service from Bezeqint via Bezeq DSL.  We got a new router
> in February, which will become relevant shortly.
>
> all our devices are configured to keep time synched automatically.  For
> the windows 7 machine, we installed a third-party time-keeping software
> instead o fallowing Windows to sync once a week.
>
> all was working fine until I realised a couple of weeks ago that the
> windows machine was over 30 seconds slow.  Due to the time-keeping software
> installed, we were able to see that it hadn't managed to sync the time
> since 7 April.
>
> I initially blamed Windows and the fact that I was running software that
> hadn't been updated in ten years.  But installing a windows port of NTP
> didn't fix things.
>
> I then realised that my Linux machines weren't keeping time either.   They
> simply hadn't drifted as far, as Linux is better at keeping time.  The macs
> weren't either.
>
> To cut a long lot of investigations short, I determined that I couldn't
> sync time using ntpd on port 123.  The only way I could get time sync to
> work was to use ntpdate with an unprivileged port.
>
> I did some searching, and found a post (that I apparently didn't bookmark)
> that suggested that some sites block NTP traffic in order to prevent
> certain types of DOS attacks.  Users at such sites are expected to use NTP
> server(s) located within the network.
>
> Since I tried a range of servers in a range of locations with no luck, I
> wondered if Bezeqint were doing the same thing.
>
> I managed to find time.bezeqint.net but it doesn't seem to work either.
>
> I called Bezeqint and had some difficulty explaining my problem to them in
> English.  When I did finally manage to get someone who knew what NTP is,
> they thought it might be  a problem with the router.  While this is
> possible, we got the router almost two months before the problem started.
>
> I expect I might get a similar answer if I call them back again, and if I
> do call Bezeq about it, I expect them to blame Bezeqint and so-on.
>
> Since nothing has changed in the last two weeks, I thought I might do
> better by asking here.
>
> So I'm wondering:
>
> 1.  Is anyone else having this problem?
>
> 2.  Has anyone found a server that works?
>
> 3.  Any other ideas I've not thought of?
>
>
I've had a similar problem on my laptop and I solved it by running "ntpdate
-u" (Where "-u" tells it to use the unprivileged port which is also used by
the "-d" flag which worked) instead of a regular "ntpdate". I'm telling it
to inform everybody.

Regards,

-- Shlomi Fish


------------------------------------------
Shlomi Fish http://www.shlomifish.org/

Chuck Norris helps the gods that help themselves.

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