[ntp:questions] Severe time drift for Undisciplined Local Clock

Richard B. gilbert rgilbert88 at comcast.net
Wed Apr 11 02:04:36 UTC 2007


deon at nulan.co.za wrote:
> Hi All
> 
> Thanks for the tremendous response I have received. I have bowed to  the 
> collective wisdom and have located a  Windows XP machine at each  of our 
> 200+ sites which we have configured to serve as a Time server.  It is 
> using the onboard RTC as the source.
> 
> I still have a problem though.
> 
> I can ping the server and Linux sees it but the time is not synched. I  
> have run ntpq and the rv command indicates that the server is  rejected. 
> Why I cannot establish. The complete log files are attached.  Anyone 
> else which can offer a reason? BTW, have tried from 2 different  servers 
> and get the same results so either I am doing something wrong  or XP has 
> a problem. (The only problem I am aware of on XP is when it  is used to 
> synch to External Clock Sources).
> 
> 
> I am calling ntpd like this:
> 
> ntpd -A -l /var/log/ntp/main.log
> 
> My /etc/ntp.conf file has one line:
> 
> server 192.168.222.100
> 
> Any help appreciated!
> 
> Deon
> 
> 
> 
> ------------------------------------------------------------------------
> 
> ntpq> pe
>      remote           refid      st t when poll reach   delay   offset  jitter
> ==============================================================================
>  192.168.222.100 .LOCL.           1 u   55   64  377    0.327  -418554 147.741
> ntpq> as
> 

<snip>

Try starting ntpd with the -g option.  That should set the time 
unconditionally. The offset is HUGE.  So is the jitter.   How long did 
you wait, after starting ntpd, before you took that ntpq display? 
Normally you should wait at least thirty minutes.

Note that the display shows that NO server has been selected as the 
synchronization source.  IOW, you gave it only one source and ntpd 
believes that that source is not suitable.  The high value for jitter 
might have something to do with that.

Using the "iburst" keyword should give you faster startup when you get 
your other problems resolved; e.g.
server 192.168.222.100 iburst




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