From: "milton_aupperle" <milton@outcastsoft.com>

Date: October 5, 2009 12:18:41 AM MDT

To: Astro_IIDC@yahoogroups.com

Subject: Re: Getting more accurate system clock times.


Hi Rodolphe;


Actually I've found it's not a firewall issue and looks to be an OS X 10.5.8 issue.


If I have the "set date & Time Automatically" check box checked and I execute the "ntptrace" command in the terminal, it will work:


localhost: stratum 16, offset 0.000000, synch distance 0.000390


If I uncheck it and then use ntptrace, it timeouts because it isn't in auto mode.


It also will not allow you to use ntpdate if it's in Auto mode, and will return a socket in use error.


TTYL..


Milton Aupperle


--- In Astro_IIDC@yahoogroups.com, Rodolphe Pineau <pineau@...> wrote:



On Sun 10/4/09, at 17:59, milton_aupperle wrote:


Hi Rodolphe;


The issue I have with ntptrace is that it times out a lot on my  

Machines. I rarely ever get anything back except:


nothing received

***Request timed out


I'm not sure if it's because I have a fire wall enabled on my router  

or if the NTP server is too busy, but I find it not reliable.


TTYL..


Milton Aupperle



It is probably a firewall issue as the NTP protocol require port 123  

(udp and tcp) to be open as the return channel for ntp queries uses  

the same port.


my example was done from behind a firewall (cisco router with nat  

enabled and access list to filter incoming packet) so unless you're  

actively blocking this port it should work. It off course depend on  

the routers and the implementation of the firewall.


Regards, Rodolphe


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