Check that www.dfn.de exists for IPv4 in case we have a typo on the domain name. Use dig to query the local name server (::1).


; <<>> DiG 9.4.1-P1 <<>> +trace +all dfn.de soa
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 962
;; flags: qr ra; QUERY: 1, ANSWER: 0, AUTHORITY: 13, ADDITIONAL: 14

;; QUESTION SECTION:
;.				IN	NS

;; AUTHORITY SECTION:
.			3600000	IN	NS	G.ROOT-SERVERS.NET.
.			3600000	IN	NS	L.ROOT-SERVERS.NET.
.			3600000	IN	NS	K.ROOT-SERVERS.NET.
.			3600000	IN	NS	F.ROOT-SERVERS.NET.
.			3600000	IN	NS	I.ROOT-SERVERS.NET.
.			3600000	IN	NS	C.ROOT-SERVERS.NET.
.			3600000	IN	NS	D.ROOT-SERVERS.NET.
.			3600000	IN	NS	A.ROOT-SERVERS.NET.
.			3600000	IN	NS	B.ROOT-SERVERS.NET.
.			3600000	IN	NS	J.ROOT-SERVERS.NET.
.			3600000	IN	NS	M.ROOT-SERVERS.NET.
.			3600000	IN	NS	E.ROOT-SERVERS.NET.
.			3600000	IN	NS	H.ROOT-SERVERS.NET.

;; ADDITIONAL SECTION:
A.ROOT-SERVERS.NET.	456419	IN	A	198.41.0.4
A.ROOT-SERVERS.NET.	456419	IN	AAAA	2001:503:ba3e::2:30
B.ROOT-SERVERS.NET.	414683	IN	A	192.228.79.201
C.ROOT-SERVERS.NET.	157077	IN	A	192.33.4.12
D.ROOT-SERVERS.NET.	153631	IN	A	128.8.10.90
D.ROOT-SERVERS.NET.	153631	IN	AAAA	2001:500:2d::d
E.ROOT-SERVERS.NET.	412003	IN	A	192.203.230.10
F.ROOT-SERVERS.NET.	457290	IN	A	192.5.5.241
F.ROOT-SERVERS.NET.	153026	IN	AAAA	2001:500:2f::f
G.ROOT-SERVERS.NET.	457954	IN	A	192.112.36.4
H.ROOT-SERVERS.NET.	414992	IN	A	128.63.2.53
H.ROOT-SERVERS.NET.	414992	IN	AAAA	2001:500:1::803f:235
I.ROOT-SERVERS.NET.	456526	IN	A	192.36.148.17
I.ROOT-SERVERS.NET.	456526	IN	AAAA	2001:7fe::53

;; Query time: 7 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Fri May 18 07:13:05 2012
;; MSG SIZE  rcvd: 512

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 2019
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 6, ADDITIONAL: 10

;; QUESTION SECTION:
;dfn.de.				IN	SOA

;; AUTHORITY SECTION:
de.			172800	IN	NS	n.de.net.
de.			172800	IN	NS	a.nic.de.
de.			172800	IN	NS	l.de.net.
de.			172800	IN	NS	f.nic.de.
de.			172800	IN	NS	s.de.net.
de.			172800	IN	NS	z.nic.de.

;; ADDITIONAL SECTION:
a.nic.de.		172800	IN	A	194.0.0.53
a.nic.de.		172800	IN	AAAA	2001:678:2::53
f.nic.de.		172800	IN	A	81.91.164.5
f.nic.de.		172800	IN	AAAA	2a02:568:0:2::53
l.de.net.		172800	IN	A	77.67.63.105
l.de.net.		172800	IN	AAAA	2001:668:1f:11::105
n.de.net.		172800	IN	A	194.146.107.6
n.de.net.		172800	IN	AAAA	2001:67c:1011:1::53
s.de.net.		172800	IN	A	195.243.137.26
z.nic.de.		172800	IN	A	194.246.96.1

;; Query time: 134 msec
;; SERVER: 2001:503:c27::2:30#53(J.ROOT-SERVERS.NET)
;; WHEN: Fri May 18 07:13:05 2012
;; MSG SIZE  rcvd: 338

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 680
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 5, ADDITIONAL: 5

;; QUESTION SECTION:
;dfn.de.				IN	SOA

;; AUTHORITY SECTION:
dfn.de.			86400	IN	NS	ns.tu-berlin.de.
dfn.de.			86400	IN	NS	deneb.dfn.de.
dfn.de.			86400	IN	NS	ws-fra1.win-ip.dfn.de.
dfn.de.			86400	IN	NS	ws-kar1.win-ip.dfn.de.
dfn.de.			86400	IN	NS	ws-mue1.win-ip.dfn.de.

;; ADDITIONAL SECTION:
ns.tu-berlin.de.	86400	IN	A	130.149.7.7
deneb.dfn.de.		86400	IN	A	192.76.176.9
ws-fra1.win-ip.dfn.de.	86400	IN	A	193.174.75.178
ws-kar1.win-ip.dfn.de.	86400	IN	A	193.174.75.154
ws-mue1.win-ip.dfn.de.	86400	IN	A	193.174.75.166

;; Query time: 123 msec
;; SERVER: 2001:67c:1011:1::53#53(n.de.net)
;; WHEN: Fri May 18 07:13:05 2012
;; MSG SIZE  rcvd: 230

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1805
;; flags: qr aa; QUERY: 1, ANSWER: 1, AUTHORITY: 5, ADDITIONAL: 5

;; QUESTION SECTION:
;dfn.de.				IN	SOA

;; ANSWER SECTION:
dfn.de.			3600	IN	SOA	deneb.dfn.de. hostmaster.dfn.de. 2012051500 28800 7200 3024000 3600

;; AUTHORITY SECTION:
dfn.de.			86400	IN	NS	ws-mue1.win-ip.dfn.de.
dfn.de.			86400	IN	NS	deneb.dfn.de.
dfn.de.			86400	IN	NS	ws-kar1.win-ip.dfn.de.
dfn.de.			86400	IN	NS	ws-fra1.win-ip.dfn.de.
dfn.de.			86400	IN	NS	ns.tu-berlin.de.

;; ADDITIONAL SECTION:
ns.tu-berlin.de.	28800	IN	A	130.149.7.7
deneb.dfn.de.		86400	IN	A	192.76.176.9
ws-fra1.win-ip.dfn.de.	86400	IN	A	193.174.75.178
ws-kar1.win-ip.dfn.de.	86400	IN	A	193.174.75.154
ws-mue1.win-ip.dfn.de.	86400	IN	A	193.174.75.166

;; Query time: 323 msec
;; SERVER: 193.174.75.178#53(ws-fra1.win-ip.dfn.de)
;; WHEN: Fri May 18 07:13:06 2012
;; MSG SIZE  rcvd: 271

HTTP

Looking for CNAME of www.dfn.de
Checking if there is a AAAA for www.dfn.de ... success.
Sending...

HEAD / HTTP/1.1
Host: www.dfn.de
User-Agent: ipv6-survey.pl/1.97 http://www.mrp.net/IPv6_Survey.html

Reading ...

HTTP/1.1 200 OK
Date: Thu, 17 May 2012 21:43:08 GMT
Server: Apache
X-Powered-By: PHP/5.3.3-7+squeeze9
Set-Cookie: fe_typo_user=1b584fdebb76d60af288ff2113bc7e76; path=/
Vary: Accept-Encoding
Content-Type: text/html; charset=iso-8859-1

Accessed / [2001:638:d:c101:acdc:1979:3:1008] Response: HTTP/1.1 200 OK

SMTP

MX 10 mfilter-100-1-2.mx.srv.dfn.de
Looking for AAAA on mfilter-100-1-2.mx.srv.dfn.de
Connecting to 2001:638:d:c302:acdc:1979:2:1 ... failed. IO::Socket::INET6: connect: Connection refused
MX 10 mfilter-100-1-3.mx.srv.dfn.de
Looking for AAAA on mfilter-100-1-3.mx.srv.dfn.de
Connecting to 2001:638:d:c303:acdc:1979:2:1 ... done.
220 mfilter-100-1-3.mx.srv.dfn.de ESMTP Postfix (Debian/GNU)
250-mfilter-100-1-3.mx.srv.dfn.de
250-PIPELINING
250-SIZE 52428800
250-ETRN
250-ENHANCEDSTATUSCODES
250 8BITMIME
MX 10 mfilter-100-1-1.mx.srv.dfn.de
Looking for AAAA on mfilter-100-1-1.mx.srv.dfn.de
Connecting to 2001:638:d:c301:acdc:1979:2:1 ... done.
220 mfilter-100-1-1.mx.srv.dfn.de ESMTP Postfix (Debian/GNU)
250-mfilter-100-1-1.mx.srv.dfn.de
250-PIPELINING
250-SIZE 52428800
250-ETRN
250-ENHANCEDSTATUSCODES
250 8BITMIME

DNS

Looking for AAAA of NS ws-mue1.win-ip.dfn.de
No AAAA record for ws-mue1.win-ip.dfn.de
Looking for AAAA of NS ws-fra1.win-ip.dfn.de
No AAAA record for ws-fra1.win-ip.dfn.de
Looking for AAAA of NS ns.tu-berlin.de
No AAAA record for ns.tu-berlin.de
Looking for AAAA of NS deneb.dfn.de
No AAAA record for deneb.dfn.de
Looking for AAAA of NS ws-kar1.win-ip.dfn.de
No AAAA record for ws-kar1.win-ip.dfn.de

NTP

Looking for an A record for ntp.dfn.de
Looking for an A record for clock.dfn.de
Looking for an A record for time.dfn.de
Looking for an A record for chime.dfn.de

XMPP

Looking for a SRV record for _xmpp-client._tcp.dfn.de
Found XMPP client focus.sgs.dfn.de (5, 5222)
Trying to connect to 194.95.237.2 on 5222 ... Connection succeeded
Trying to connect to 2001:638:206:4:0:0:0:2 on 5222 ... Can't bind to port: IO::Socket::INET6: connect: Connection refused

Looking for a SRV record for _xmpp-server._tcp.dfn.de
Found XMPP server focus.sgs.dfn.de (5, 5269)
Trying to connect to 194.95.237.2 on 5269 ... Connection succeeded
Trying to connect to 2001:638:206:4:0:0:0:2 on 5269 ... Can't bind to port: IO::Socket::INET6: connect: Connection refused

Last Updated: Thu May 17 21:43:20 2012 UTC