[ntp:questions] hello, I have a question about NTPD service in LAN use a host as time source two other host as client

unruh unruh at invalid.ca
Thu Jun 13 17:47:17 UTC 2013

On 2013-06-13, xiaoniao54321 at gmail.com <xiaoniao54321 at gmail.com> wrote:
> I?v recently start a work about NTP,it's about a ntp sync in 
> winodws LAN,no GPS,only a host as server,two host as client.But Ican't sync 
> the time ,because the server clock and reftime is not the same.I use ntpq-c 
> rv to query the time,but I,v got a different reftime and clock,especially I 
> adjust  the server time to a time before it .
> I had run ntpq -c rv on CMD.it shows lisk:
> reftime=d5639c52.13c08ef6 thu,jun 13 2012 9:18:10:077,pool=10,
> clock=d5639c68.5717350d thu,jun 13 2012 9:18:10:340,state=4,
> offset=0.000,frequency=0.000,jitter=0.000,noise=0.000,stability=0.000,tai=0
> I know that the clock above shows system clock of host as time source,
> but if the clock item up shows the current system time,when I changed  the clock below on the right taskbar of my system to 9:01.set local host as time source, 
> run ntpq -c rv on cmd but the clock item didn't changed to 9:01,that's why?

Why should it? ntpd does not simply change the time on the host to agree
with the server. It first checks for a long time to make sure that the
time from the server is really correct, and has not been corrupted (it
takes at least 8 measurement cycles to do that) only then will it jump
the clock (if it is out by more than .128 sec).

ntpd operates slowly. 


More information about the questions mailing list