[ntp:questions] IPv6 vs IPv4 look-ups (Was: Re: http://www.ntp.org/ => a blank page?)

Steve Kostecke kostecke at ntp.org
Thu Mar 5 13:42:14 UTC 2009

On 2009-03-05, Martin Burnicki <martin.burnicki at meinberg.de> wrote:

> The IPv4 address is used only after the IPv6 address has timed out, even
> though (as far as I understand it) the DNS server first returns an IPv4
> address, then an IPv6 address:
> # host support.ntp.org
> support.ntp.org has address
> support.ntp.org has IPv6 address 2001:4f8:0:2::23

On my LAN I see:

$ host support.ntp.org
support.ntp.org     	A

To resolve the IPv6 address:

$ aaaa support.ntp.org
support.ntp.org     	AAAA	2001:4F8:0:2:0:0:0:23

Both 'host' and 'aaaa' are a part of the Debian host package. The
version I have installed is:

||/ Name         Version       Description
ii  host         20000331-9    utility for querying DNS servers

If it matters I run a local name-server and do have a 6-to-4 tunnel.

Steve Kostecke <kostecke at ntp.org>
NTP Public Services Project - http://support.ntp.org/

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