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[ntpwg] NTP daemons and DNS (question)

Marco Davids <Marco.Davids@sidn.nl> Wed, 24 July 2019 17:40 UTC

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From: Marco Davids <Marco.Davids@sidn.nl>
To: "ntpwg@ietf.org" <ntpwg@ietf.org>
Thread-Topic: NTP daemons and DNS (question)
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Date: Wed, 24 Jul 2019 17:40:11 +0000
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Subject: [ntpwg] NTP daemons and DNS (question)
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Hi,

I'm trying to understand how various NTP daemons handle DNS.

Will they perform a DNS lookup each time they are about to poll a
server?

Or do they lookup and store the IP address of an NTP server in ntp.conf
once when they start and keep using that forever?

Or something in between perhaps?

I tried to figure this out with TCPdump, but my findings where not
conclusive enough.

Thanks.

-- 
Marco

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