Check that www.postech.ac.kr 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 postech.ac.kr soa
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 620
;; flags: qr ra; QUERY: 1, ANSWER: 13, AUTHORITY: 0, ADDITIONAL: 14

;; QUESTION SECTION:
;.				IN	NS

;; ANSWER SECTION:
.			220244	IN	NS	i.root-servers.net.
.			220244	IN	NS	g.root-servers.net.
.			220244	IN	NS	c.root-servers.net.
.			220244	IN	NS	m.root-servers.net.
.			220244	IN	NS	d.root-servers.net.
.			220244	IN	NS	h.root-servers.net.
.			220244	IN	NS	f.root-servers.net.
.			220244	IN	NS	j.root-servers.net.
.			220244	IN	NS	l.root-servers.net.
.			220244	IN	NS	a.root-servers.net.
.			220244	IN	NS	b.root-servers.net.
.			220244	IN	NS	k.root-servers.net.
.			220244	IN	NS	e.root-servers.net.

;; ADDITIONAL SECTION:
a.root-servers.net.	89567	IN	A	198.41.0.4
a.root-servers.net.	89567	IN	AAAA	2001:503:ba3e::2:30
b.root-servers.net.	47831	IN	A	192.228.79.201
c.root-servers.net.	435615	IN	A	192.33.4.12
d.root-servers.net.	393964	IN	A	128.8.10.90
d.root-servers.net.	393964	IN	AAAA	2001:500:2d::d
e.root-servers.net.	45151	IN	A	192.203.230.10
f.root-servers.net.	90438	IN	A	192.5.5.241
f.root-servers.net.	395314	IN	AAAA	2001:500:2f::f
g.root-servers.net.	91102	IN	A	192.112.36.4
h.root-servers.net.	48140	IN	A	128.63.2.53
h.root-servers.net.	48140	IN	AAAA	2001:500:1::803f:235
i.root-servers.net.	89674	IN	A	192.36.148.17
i.root-servers.net.	89674	IN	AAAA	2001:7fe::53

;; Query time: 7 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Tue May 22 13:07:17 2012
;; MSG SIZE  rcvd: 512

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1268
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 6, ADDITIONAL: 8

;; QUESTION SECTION:
;postech.ac.kr.			IN	SOA

;; AUTHORITY SECTION:
kr.			172800	IN	NS	e.dns.kr.
kr.			172800	IN	NS	f.dns.kr.
kr.			172800	IN	NS	g.dns.kr.
kr.			172800	IN	NS	c.dns.kr.
kr.			172800	IN	NS	b.dns.kr.
kr.			172800	IN	NS	d.dns.kr.

;; ADDITIONAL SECTION:
b.dns.kr.		172800	IN	A	61.74.75.1
c.dns.kr.		172800	IN	A	203.248.246.220
d.dns.kr.		172800	IN	A	203.83.159.1
e.dns.kr.		172800	IN	A	202.30.124.100
f.dns.kr.		172800	IN	A	218.38.181.90
g.dns.kr.		172800	IN	A	202.31.190.1
e.dns.kr.		172800	IN	AAAA	2001:dcc:5::100
g.dns.kr.		172800	IN	AAAA	2001:dc5:a::1

;; Query time: 128 msec
;; SERVER: 192.112.36.4#53(g.root-servers.net)
;; WHEN: Tue May 22 13:07:17 2012
;; MSG SIZE  rcvd: 283

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 709
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;postech.ac.kr.			IN	SOA

;; AUTHORITY SECTION:
postech.ac.kr.		86400	IN	NS	ns2.postech.ac.kr.
postech.ac.kr.		86400	IN	NS	ns.postech.ac.kr.

;; ADDITIONAL SECTION:
ns.postech.ac.kr.	86400	IN	A	141.223.1.2
ns2.postech.ac.kr.	86400	IN	A	141.223.7.51

;; Query time: 250 msec
;; SERVER: 218.38.181.90#53(f.dns.kr)
;; WHEN: Tue May 22 13:07:17 2012
;; MSG SIZE  rcvd: 98

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 351
;; flags: qr aa; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;postech.ac.kr.			IN	SOA

;; ANSWER SECTION:
postech.ac.kr.		172800	IN	SOA	ns.postech.ac.kr. domain.postech.ac.kr. 2012052101 10800 3600 604800 86400

;; AUTHORITY SECTION:
postech.ac.kr.		172800	IN	NS	ns.postech.ac.kr.
postech.ac.kr.		172800	IN	NS	ns2.postech.ac.kr.

;; ADDITIONAL SECTION:
ns.postech.ac.kr.	172800	IN	A	141.223.1.2
ns2.postech.ac.kr.	172800	IN	A	141.223.7.51

;; Query time: 333 msec
;; SERVER: 141.223.1.2#53(ns.postech.ac.kr)
;; WHEN: Tue May 22 13:07:18 2012
;; MSG SIZE  rcvd: 141

HTTP

Looking for CNAME of www.postech.ac.kr
Checking if there is a AAAA for www.postech.ac.kr ... FAILED.


; <<>> DiG 9.4.1-P1 <<>> www.postech.ac.kr aaaa
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1066
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;www.postech.ac.kr.		IN	AAAA

;; AUTHORITY SECTION:
postech.ac.kr.		10800	IN	SOA	ns.postech.ac.kr. domain.postech.ac.kr. 2012052101 10800 3600 604800 86400

;; Query time: 4 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Tue May 22 13:07:20 2012
;; MSG SIZE  rcvd: 81

Checking other options ... failed too.

SMTP

MX 5 spam.postech.ac.kr
Looking for AAAA on spam.postech.ac.kr

DNS

Looking for AAAA of NS ns2.postech.ac.kr
No AAAA record for ns2.postech.ac.kr
Looking for AAAA of NS ns.postech.ac.kr
No AAAA record for ns.postech.ac.kr

NTP

Looking for an A record for ntp.postech.ac.kr
Found an A or AAAA record. Now looking for a AAAA.
Cannot find a AAAA record for ntp.postech.ac.kr
Cannot find a AAAA record for ntp.ipv6.postech.ac.kr

XMPP

Looking for a SRV record for _xmpp-client._tcp.postech.ac.kr
Looking for a SRV record for _xmpp-server._tcp.postech.ac.kr

Last Updated: Tue May 22 03:37:23 2012 UTC