Different behaviour for different TLDs?

[Barry Margolin]

In article <blkbib$1sn5$1 at sf1.isc.org>,
Konrad Lienhard <konrad.lienhard at remove_darki.ch> wrote:
>Hello
>
>I created a subdomain (with separate dns server responsible for it)
>However I have a problem with it. I narrowed it down to the problem that the
>TLD's for .com are responding different than e.g. the TLD for .ch:
>
>(merapi.switch.ch is a TLD for .ch)
>--------------------------------
>> migze020.migros.ch
>Server:  merapi.switch.ch
>Address:  130.59.211.10
>
>Name:    migze020.migros.ch
>Served by:
>- migze020.migros.ch
>          193.5.175.194
>          migros.ch
>- migze030.migros.ch
>          193.5.175.195
>          migros.ch
>---------------------------------
>(b.gtld-servers.net is a TLD for .com)
>
>> ns.swisscom.com
>Server:  b.gtld-servers.net
>Address:  192.33.14.30
>
>Non-authoritative answer:
>Name:    ns.swisscom.com
>Address:  138.190.1.12
>---------------------------------
>
>So it seems that the .com TLD are caching the ip's of the different
>domainservers. (I know they have to know these ip's but to my understanding
>the answer from the .ch TLD is "more" correct because a TLD should only
>delegating and not answering directly.

I don't understand the problem you're reporting.  You asked the servers
completely different questions, so of course they gave different answers.
You asked the .ch server for migze020.migros.ch, and you asked the .com
server for ns.swisscom.com.

Anyway, the usual explanation for a TLD server giving a different A record
than the authoritative server for the subdomain is that there's a Host
registration for the server, e.g. 

% whois -h whois.internic.net ns.swisscom.com

   Server Name: NS.SWISSCOM.COM
   IP Address: 138.190.1.12
   Registrar: NETWORK SOLUTIONS, INC.
   Whois Server: whois.networksolutions.com
   Referral URL: http://www.networksolutions.com

As far as I can tell, this address is correct; I queried ns1.swisscom.com
and it gave the same IP.

-- 
Barry Margolin, barry.margolin at level3.com
Level(3), Woburn, MA
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