topic Re: how to retard ntp sync in Operating System - Linux

how to retard ntp sync

Alpha977 — Thu, 04 Jan 2007 08:38:54 GMT

Hello all!

I need to know how i can to retard the ntp syncronize with the ntp server.

How i can do this?

Thank you!

(points to reply)

Re: how to retard ntp sync

Ivan Ferreira — Thu, 04 Jan 2007 09:52:08 GMT

You can use the minpoll option. See man ntp for detailed information.

Re: how to retard ntp sync

Steven E. Protter — Thu, 04 Jan 2007 09:58:18 GMT

Shalom,

service ntpd stop
or
service xntpd stop

Depending on your distribution.

You can also modify ntp.conf and restart.

SEP

Re: how to retard ntp sync

rick jones — Thu, 04 Jan 2007 20:34:02 GMT

At the risk of showing I didn't fully understand the question...

I was under the impression that as NTP achieved sync with the time server(s) it naturally backed-off on the polling interval to something like 1024 seconds, and that if it didn't back-off it suggested that NTP was having trouble establishing and/or keeping synchronization.

In that case, setting minpoll might treat a symptom of sending many queries, but not a root cause...

Re: how to retard ntp sync

Alpha977 — Fri, 05 Jan 2007 04:29:48 GMT

Thanks to all for the reply.

Now i need to know how configure the minpool, because i don't find it on the man page.

Thanks!

Re: how to retard ntp sync

Charles Holland — Fri, 05 Jan 2007 07:34:30 GMT

The minpoll is an option in your /etc/ntp.conf file. Review your ntp.conf and you will be able to figure it out. To make it active you will need to stop/start your ntp process.

Regards

Re: how to retard ntp sync

Charles Holland — Fri, 05 Jan 2007 07:57:20 GMT

Well I first thought you were talking about HPUX but then realized you were talking about Linux. Anyway it is basically the same thing. Here is an example out of my /usr/share/doc/packages/xntp/conf directory were I simply did a grep for poll I found both minpoll and maxpoll entries.

minpoll:
server 127.127.22.1 minpoll 4 # PPS quick poll

maxpoll:
manycastclient 239.1.1.1 autokey maxpoll 12 ttl 7

Now if minpoll is indicating that it will attempt ever 4 seconds to sync, and maxpoll it that it will go to 12 seconds before trying to sync how does it manage to get to a 1024 polling (slightly over 17 minutes) interval as represented by
# ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
LOCAL(0) LOCAL(0) 10 l 35 64 377 0.000 0.000 0.004
*server1 tick.usno.navy. 2 u 687 1024 377 0.256 -2.726 0.068
+server2 bonehed.lcs.mit 2 u 691 1024 377 0.393 -2.202 0.568

Perhaps because I don't have either min nor max in my /etc/ntp.conf file. There is probably a maximum you can specify. I might suggest that you explore http://www.eecis.udel.edu/~ntp for further answers.

Regards

Re: how to retard ntp sync

Alpha977 — Fri, 05 Jan 2007 08:42:30 GMT

Thank Charles for your reply!

I'm looking for this!

Thanks again!

Regards