Re: [gentoo-user] Server system date synchronizaion

[Alan McKinnon <alan.mckinnon@gmail.com>]

On 26/04/2013 23:28, Nick Khamis wrote:
> On 4/26/13, Alan McKinnon <alan.mckinnon@gmail.com> wrote:
>> On 26/04/2013 19:11, Nick Khamis wrote:
>>>>>>> Thank you so much for your response, and I totally understand the
>>>>>>> effort vs. benefit challenge. However, is it really that much
>>>>>>> trouble/unstable to setup our own ntp
>>>>>>> server that syncs with our local isp, and have our internal network
>>>>>>> sync
>>>>>>> on it?
>>>>>
>>>>>
>>>>> No, it's not THAT much effort. You can get by with installing ntpd on
>>>>> a
>>>>> single machine, pointing it at the upstream time server and pointing
>>>>> all
>>>>> your clients to it. It's clearly recorded in the config file, you
>>>>> can't
>>>>> go wrong.
>>>>>
>>>>> It's understanding how this weird thing called time works that is the
>>>>> issue. Take for example leap seconds..... urggggggggggg...
>>>>>
>>>>> The basic question I suppose is why do you want to do it this way?
>>>>> What
>>>>> do you feel you will gain by doing it yourself?
>>>>>
>>>>>
>>>>> --
>>>>> Alan McKinnon
>>>>> alan.mckinnon@gmail.com
>>>>>
>>>>>
>>>>>
>>> Hello Alan,
>>>
>>> Thank you so much for your time. Our voip cluster time always vary for
>>> some reason....
>>> And with long distance, that could mean upwards to a dollar a call.
>>
>>
>> Ah, OK. That changes things quite a bit. I have a little bit of
>> experience with that - I work for a large ISP, we have a large VOIP
>> department and we run a stratum 2 time server that serves most of the
>> country.
>>
>> First things first: you can't just stick any old upstream ntp server in
>> your config and walk away. You are then reliant on the quality of that
>> upstream, and far too often other time servers operate on a "good
>> enough" policy - if it's accurate to about a second, it's good enough
>> (and for desktop users i.e. most ISP clients, it is good enough).
>>
>> I don't know how big your operation is, if you have budget I suggest you
>> invest in a proper master time source that is GPS-driven. We have a
>> Symmetricom (http://www.symmetricom.com) but it's a mature market with
>> several vendors. Shop around, prices are less than you'd expect (about
>> the same as a decent mid-range server and much less than Cisco's
>> routers...)
>>
>> Weather can get in the way, so back up the device with a decent second
>> upstream. I have a good one available run by the Science and Technology
>> Research part of the Dept of Trade and Industry and the third option is
>> all the other big ISPs around.
>>
>> Depending on your accuracy needs you could get away without the GPS unit
>> and just use a good upstream, but I'd fight for the budget for it - tell
>> management it puts control of billing back in your hands, they always
>> fall for that one :-)
>>
>> So the summary would be that I reckon ntpd will do what you want as long
>> as you chose good reliable time sources. With that in hand, the config
>> is easy as rather well documented. Shout here ont he list if you need a
>> hand with this when you come to deployment time
>>
>>
>>
>>
>> --
>> Alan McKinnon
>> alan.mckinnon@gmail.com
>>
>>
>>
> 
> Any suggestions for a "reliable", use that word cautiously ntp server.
> Requests are coming from canada. Was there not a project that dealt
> with setting up a network across the globe just for serving up NTP
> services? Did that marvelous idea die out?

Isn't that what pool.ntp.org does?

As for reliable, I'm not familiar with how Canada has set itself up, but
most Western governments have a "Science and Technology" department or
NGO and most run time servers to serve the local scientific community.
They might not let you sync to their server (stratum 1 providers are
touchy) but someone will sync to it, and they in turn may provide a free
time service.

Start by Googling "stratum 1 time server Canada" and see where that
takes you. Really, this stuff isn't hard and you will be up and running
in no time. The hard part is when *you* provide a public service and
need to pay attention to the insane amount of detail inherent in this
subject.


-- 
Alan McKinnon
alan.mckinnon@gmail.com