ntpd?

[Todd Denniston]

Knute Johnson wrote, On 01/09/2008 01:40 AM:
> For some reason the ntp program is checking the time much more often 
> that it used to.  Do I have something misconfigured or is this the 
> norm?
> 

What you have in the logs below is not reports of ntp 'checking the time', it 
is ntp telling you that it has chosen a different host to be the best and 
follow, or that the system time had gotten so far out of sync with the best 
host that it had to jump time.

The time delta's between host jumps and time resets look fine to me.

To get less reporting of host jumps,
  you would need to pick hosts that are either more stable and/or closer too you,
or pick _one_ with a better stratum (this is not really recommended unless you 
require perfect time, and have an agreement to use that server),
or you could get a radio/gps receiver and have your own stratum 1 server.

Another option is one that would require direct editing of the ntp.conf, 
because fedora's gui tool does not support this, is to set the maxpoll of each 
server to a longer time and/or burst, i.e.,
server   216.106.184.58 maxpoll 12
server   208.113.193.10 burst
server   208.75.88.4    maxpoll 12 burst
Once the computer gets in sync, you should then only see host changes about 
once or twice every maxpoll.  default maxpoll is 10 which is 1024 seconds or 
17 minutes, maxpoll 12 would be about 68 minutes.

> Thanks,
> 
> knute...
> 
> Jan  6 20:06:51 www ntpd[1705]: synchronized to 216.106.184.58, 
> stratum 2
> Jan  6 21:10:00 www ntpd[1705]: synchronized to 208.113.193.10, 
> stratum 2
> Jan  6 23:26:33 www ntpd[1705]: synchronized to 208.75.88.4, stratum 
> 2
> Jan  6 23:57:32 www ntpd[1705]: time reset -0.357519 s
> Jan  7 00:03:26 www ntpd[1705]: synchronized to 208.75.88.4, stratum 
> 2
> Jan  7 00:39:57 www ntpd[1705]: synchronized to 216.106.184.58, 
> stratum 2
> Jan  7 00:40:45 www ntpd[1705]: time reset +0.173460 s
> Jan  7 00:46:55 www ntpd[1705]: synchronized to 208.113.193.10, 
> stratum 2
<SNIP>
> Jan  8 06:04:59 www ntpd[1705]: synchronized to 208.113.193.10, 
> stratum 2
> Jan  8 06:12:15 www ntpd[1705]: synchronized to 208.75.88.4, stratum 
> 2
> Jan  8 07:24:53 www ntpd[1705]: synchronized to 208.113.193.10, 
> stratum 2
> Jan  8 07:28:04 www ntpd[1705]: synchronized to 208.75.88.4, stratum 
> 2
> Jan  8 09:33:22 www ntpd[1705]: synchronized to 208.113.193.10, 
> stratum 2
> Jan  8 09:58:58 www ntpd[1705]: synchronized to 208.75.88.4, stratum 
> 2
> Jan  8 16:21:57 www ntpd[1705]: synchronized to 208.113.193.10, 
> stratum 2
> 


-- 
Todd Denniston
Crane Division, Naval Surface Warfare Center (NSWC Crane)
Harnessing the Power of Technology for the Warfighter