[ntp:questions] Re: New to NTPD

Richard B. Gilbert rgilbert88 at comcast.net
Wed May 10 13:51:41 UTC 2006


Ted Gervais wrote:

> On Tue, 9 May 2006, Richard B. Gilbert wrote:
> 
>>>      remote           refid      st t when poll reach   delay   
>>> offset jitter
>>> ============================================================================== 
>>>
>>>  mircx.com       129.6.15.29      2 u   23  128    7   70.362   
>>> 27.808 7.917
>>>  neate.neateroll 199.212.17.15    3 u   24  128    7   80.833   
>>> 14.010 6.666
>>>  d221-85-115.com 132.246.168.9    2 u   17  128    7   41.316   
>>> 25.977 2.463
>>> ----------------
>>>
>> <snip>
>>
>> Your reach field shows that only the three most recent polls were 
>> successful!!!!  This is not good.  Did you disconnect the network 
>> cable or have a network problem?  That is probably why none of the 
>> three servers has been selected.
> 
> 
> Yes.  Somehow my system rebooted??  I don't know why. But it came back 
> up and that was the result.
> 
>> Can you find a fourth server?  Four are the minimum required to 
>> protect against one falseticker.  Five protect against two 
>> falsetickers and seven against three.   With only three servers, the 
>> failure of one leaves you with only two.
> 
> 
> OK on adding another server.  Iwill do that right now. And here is what 
> things look like now that it has been running for nearly a full day:
> ---------
>      remote           refid      st t when poll reach   delay   offset 
> jitter
> ============================================================================== 
> 
> +mircx.com    207.126.98.204   2 u  288 1024  375   71.586  -100.04 45.062
> +neate.neateroll 199.212.17.20  3 u  320 1024  377   76.978  -21.913 5.698
> *d221-85-115.com 132.246.168.2  2 u  314 1024  377   42.064   -6.444 3.894
> 
> 
> 
>>  It is written that a man with two clocks can never be certain what 
>> time it is!!
>>
>> You need to let that system run for a while, perhaps for as long as a 
>> full day to reach a stable state with good synchronization.
>>
> Yes.  And of course I plan to run it forever without any breaks as I 
> have this on my server which runs all the  time anyway..
> 
> ---
> Ted Gervais
> Coldbrook, Nova Scotia
> Canada. (ve1drg)
> 

It looks as if it's working.  I wish I could say it's working well.  It 
may BE working well but I worry about the large difference of opinion 
between mircx.com and d221-85-115.com.  I suspect that at least one of 
them has a serious problem of some sort. I suppose that Nova Scotia does 
not give you a large choice of nearby servers.

ntptime should show you your "maximum error" and "estimated error".  If 
you are satisfied with those numbers you are done.  If not, you might 
look into the purchase of a hardware reference clock of some sort.  You 
can get a GPS timing receiver from Garmin (GPS18-LVC) for about $85 US.
If you get that working you become a stratum 1 server in your own right!
Depending on your hardware and O/S, you could keep your server within a 
few microseconds of UTC.




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