Re: [dhcwg] [ntpwg] Fwd: New Version Notification for draft-ogud-dhc-udp-time-option-01.txt

Sanjeev Gupta <ghane0@gmail.com> Mon, 02 December 2013 12:12 UTC

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From: Sanjeev Gupta <ghane0@gmail.com>
Date: Mon, 2 Dec 2013 20:12:29 +0800
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Cc: NTP Working Group <ntpwg@lists.ntp.org>, "dhcwg@ietf.org WG" <dhcwg@ietf.org>, Ted Lemon <ted.lemon@nominum.com>, "Bernie Volz \(volz\)" <volz@cisco.com>
Subject: Re: [dhcwg] [ntpwg] Fwd: New Version Notification for draft-ogud-dhc-udp-time-option-01.txt
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On Mon, Dec 2, 2013 at 8:31 AM, Danny Mayer <mayer@ntp.org> wrote:

> The problem is that for NTP
> DNS names are preferred over IP addresses because that allows a server
> maintainer to retire an NTP server.
>

With the "server" directive, once the FQDN is resolved by the system
resolver, ntpd will continue with tah IP address, even if the FQDN changes,
till it is restarted.

We are talking only about time at startup, right?

Then, I do not see any issues if the DHCP server specifies a IP address; as
long as the server administrator can manage to check that the IP is valid
(for a short time in the future).

1. The DHCP server administrator SHOULD specify the IP address of a valid
NTP server.

or

2. DHCP Server software MUST resolve the NTP server name to an IP address
before providing it to clients

Or am I missing something even more basic?

-- 
Sanjeev Gupta
+65 98551208     http://www.linkedin.com/in/ghane