[ntp:questions] Local clock question with dialup connection
George N. White III
gwhite at eastlink.ca
Sun Apr 15 18:37:30 UTC 2007
On Sun, 15 Apr 2007, Nigel Henry wrote:
> Ntp is working just fine since I enabled it on my Linux machines some time
> back, but as I'm on dialup, I lose the connection from time to time, and when
> I'm not DL'ing updates overnight, I usually shutdown the 2 machines on the
> The 2 machines are connected to the Internet through a Smoothwall firewall,
> and a serial modem. One machine, with whichever distro is running on it, has
> ntp.conf setup to access 3 stratum 2 Internet time servers, and the other
> machine has ntp.conf setup to get it's time from the first machine which is
> accessing the Internet timeservers.
> The problem I have is that when, for example, I lose the Internet connection
> during the night doing updates, then reconnect the next morning, I find that
> ntpd is still running, but has timed out on trying to contact the Internet
> timeservers. If I stop, then restart ntpd, the timeservers are contacted ok,
> and the time is kept in sync with the servers.
> Normally I comment out everything on the default setup for ntp.conf, except
> for the servers I am using, and the driftfile, but today I installed FC6 on
> the machine I use for getting time from the Internet. As usual I commented
> out all the default stuff, but left the 2 lines for the undisciplined local
> clock uncommented.
> Ntpq> pe initially showed the local clock as sys.peer, but as soon as the
> Internet servers had obtained a sufficient reach count, the sys.peer switched
> from the local clock to one of the 3 Internet timeservers.
> My question, as a dialup user is. If I Ieave the 2 undisciplined local clock
> lines uncommented in ntp.conf, will this resolve the problem I seem to have
> when I lose the Internet connection, and ntpd goes into timeout mode when it
> can't find Internet timeservers when the connection is lost? If so, it will
> have resolved the only problem I seem to be having with ntp.
> Sorry for the trivial question.
I'm not sure ntp is the right tool. <http://chrony.sunsite.dk/>
The other major feature is if you have an intermittent (e.g. dial-up)
connection to the network where your NTP servers are. chronyd has been
specifically written to work well in this case, and it still works
well in a "permanently connected" mode.
Chronyd works reasonably well form me on dialup and wireless links (FC5
George N. White III <aa056 at chebucto.ns.ca>
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