[ntp:questions] How often does ntpd refresh its DNS lookup?

Miroslav Lichvar mlichvar at redhat.com
Mon Aug 5 10:10:29 UTC 2019

On Sat, Aug 03, 2019 at 02:38:45PM -0500, Jason Rabel wrote:
> > For server-entries in ntp.conf, how does ntpd (4.2.8p13) time refreshing
> > of hostnames?
> As far as I know, for regular server entries once it's done the
> initial lookup on startup, that's it...

Yes, that's my understanding too.

> I believe for pool entries it will do a lookup to grab new IPs if a
> pool server goes silent. Maybe that's what you were referring to?

If it's unreachable, or serving wrong time (falseticker). Not
periodically as that might cause clock hopping and possibly overload
the DNS servers.

Miroslav Lichvar

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