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On 26/04/2013 23:28, Nick Khamis wrote: |
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> On 4/26/13, Alan McKinnon <alan.mckinnon@×××××.com> wrote: |
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>> On 26/04/2013 19:11, Nick Khamis wrote: |
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>>>>>>> Thank you so much for your response, and I totally understand the |
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>>>>>>> effort vs. benefit challenge. However, is it really that much |
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>>>>>>> trouble/unstable to setup our own ntp |
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>>>>>>> server that syncs with our local isp, and have our internal network |
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>>>>>>> sync |
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>>>>>>> on it? |
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>>>>> |
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>>>>> |
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>>>>> No, it's not THAT much effort. You can get by with installing ntpd on |
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>>>>> a |
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>>>>> single machine, pointing it at the upstream time server and pointing |
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>>>>> all |
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>>>>> your clients to it. It's clearly recorded in the config file, you |
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>>>>> can't |
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>>>>> go wrong. |
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>>>>> |
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>>>>> It's understanding how this weird thing called time works that is the |
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>>>>> issue. Take for example leap seconds..... urggggggggggg... |
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>>>>> |
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>>>>> The basic question I suppose is why do you want to do it this way? |
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>>>>> What |
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>>>>> do you feel you will gain by doing it yourself? |
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>>>>> |
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>>>>> |
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>>>>> -- |
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>>>>> Alan McKinnon |
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>>>>> alan.mckinnon@×××××.com |
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>>>>> |
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>>>>> |
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>>>>> |
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>>> Hello Alan, |
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>>> |
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>>> Thank you so much for your time. Our voip cluster time always vary for |
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>>> some reason.... |
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>>> And with long distance, that could mean upwards to a dollar a call. |
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>> |
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>> |
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>> Ah, OK. That changes things quite a bit. I have a little bit of |
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>> experience with that - I work for a large ISP, we have a large VOIP |
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>> department and we run a stratum 2 time server that serves most of the |
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>> country. |
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>> |
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>> First things first: you can't just stick any old upstream ntp server in |
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>> your config and walk away. You are then reliant on the quality of that |
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>> upstream, and far too often other time servers operate on a "good |
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>> enough" policy - if it's accurate to about a second, it's good enough |
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>> (and for desktop users i.e. most ISP clients, it is good enough). |
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>> |
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>> I don't know how big your operation is, if you have budget I suggest you |
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>> invest in a proper master time source that is GPS-driven. We have a |
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>> Symmetricom (http://www.symmetricom.com) but it's a mature market with |
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>> several vendors. Shop around, prices are less than you'd expect (about |
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>> the same as a decent mid-range server and much less than Cisco's |
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>> routers...) |
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>> |
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>> Weather can get in the way, so back up the device with a decent second |
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>> upstream. I have a good one available run by the Science and Technology |
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>> Research part of the Dept of Trade and Industry and the third option is |
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>> all the other big ISPs around. |
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>> |
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>> Depending on your accuracy needs you could get away without the GPS unit |
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>> and just use a good upstream, but I'd fight for the budget for it - tell |
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>> management it puts control of billing back in your hands, they always |
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>> fall for that one :-) |
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>> |
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>> So the summary would be that I reckon ntpd will do what you want as long |
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>> as you chose good reliable time sources. With that in hand, the config |
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>> is easy as rather well documented. Shout here ont he list if you need a |
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>> hand with this when you come to deployment time |
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>> |
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>> |
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>> |
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>> |
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>> -- |
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>> Alan McKinnon |
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>> alan.mckinnon@×××××.com |
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>> |
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>> |
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>> |
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> |
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> Any suggestions for a "reliable", use that word cautiously ntp server. |
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> Requests are coming from canada. Was there not a project that dealt |
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> with setting up a network across the globe just for serving up NTP |
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> services? Did that marvelous idea die out? |
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|
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Isn't that what pool.ntp.org does? |
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As for reliable, I'm not familiar with how Canada has set itself up, but |
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most Western governments have a "Science and Technology" department or |
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NGO and most run time servers to serve the local scientific community. |
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They might not let you sync to their server (stratum 1 providers are |
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touchy) but someone will sync to it, and they in turn may provide a free |
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time service. |
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|
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Start by Googling "stratum 1 time server Canada" and see where that |
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takes you. Really, this stuff isn't hard and you will be up and running |
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in no time. The hard part is when *you* provide a public service and |
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need to pay attention to the insane amount of detail inherent in this |
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subject. |
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-- |
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Alan McKinnon |
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alan.mckinnon@×××××.com |
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