Check that www.ied.edu.hk 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 ied.edu.hk soa
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 228
;; flags: qr ra; QUERY: 1, ANSWER: 13, AUTHORITY: 0, ADDITIONAL: 14

;; QUESTION SECTION:
;.				IN	NS

;; ANSWER SECTION:
.			311809	IN	NS	c.root-servers.net.
.			311809	IN	NS	m.root-servers.net.
.			311809	IN	NS	d.root-servers.net.
.			311809	IN	NS	g.root-servers.net.
.			311809	IN	NS	e.root-servers.net.
.			311809	IN	NS	a.root-servers.net.
.			311809	IN	NS	k.root-servers.net.
.			311809	IN	NS	i.root-servers.net.
.			311809	IN	NS	f.root-servers.net.
.			311809	IN	NS	h.root-servers.net.
.			311809	IN	NS	l.root-servers.net.
.			311809	IN	NS	b.root-servers.net.
.			311809	IN	NS	j.root-servers.net.

;; ADDITIONAL SECTION:
a.root-servers.net.	181132	IN	A	198.41.0.4
a.root-servers.net.	181132	IN	AAAA	2001:503:ba3e::2:30
b.root-servers.net.	139396	IN	A	192.228.79.201
c.root-servers.net.	527180	IN	A	192.33.4.12
d.root-servers.net.	485529	IN	A	128.8.10.90
d.root-servers.net.	485529	IN	AAAA	2001:500:2d::d
e.root-servers.net.	136716	IN	A	192.203.230.10
f.root-servers.net.	182003	IN	A	192.5.5.241
f.root-servers.net.	486879	IN	AAAA	2001:500:2f::f
g.root-servers.net.	182667	IN	A	192.112.36.4
h.root-servers.net.	139705	IN	A	128.63.2.53
h.root-servers.net.	139705	IN	AAAA	2001:500:1::803f:235
i.root-servers.net.	181239	IN	A	192.36.148.17
i.root-servers.net.	181239	IN	AAAA	2001:7fe::53

;; Query time: 7 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Mon May 21 11:41:12 2012
;; MSG SIZE  rcvd: 512

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 314
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 8, ADDITIONAL: 13

;; QUESTION SECTION:
;ied.edu.hk.			IN	SOA

;; AUTHORITY SECTION:
hk.			172800	IN	NS	adns1.berkeley.edu.
hk.			172800	IN	NS	z.hkirc.net.hk.
hk.			172800	IN	NS	ns1.hkirc.net.hk.
hk.			172800	IN	NS	b.dns.tw.
hk.			172800	IN	NS	sec3.apnic.net.
hk.			172800	IN	NS	hk-ns.pch.net.
hk.			172800	IN	NS	ns2.hkirc.net.hk.
hk.			172800	IN	NS	ns2.cuhk.edu.hk.

;; ADDITIONAL SECTION:
b.dns.tw.		172800	IN	A	210.201.138.58
z.hkirc.net.hk.		172800	IN	A	194.146.106.70
ns1.hkirc.net.hk.	172800	IN	A	203.119.2.18
ns2.cuhk.edu.hk.	172800	IN	A	137.189.6.21
ns2.hkirc.net.hk.	172800	IN	A	203.119.87.19
sec3.apnic.net.		172800	IN	A	202.12.28.140
adns1.berkeley.edu.	172800	IN	A	128.32.136.3
hk-ns.pch.net.		172800	IN	A	204.61.216.46
b.dns.tw.		172800	IN	AAAA	2404:0:10a0::58
z.hkirc.net.hk.		172800	IN	AAAA	2001:67c:1010:17::53
ns2.cuhk.edu.hk.	172800	IN	AAAA	2405:3000:3:60::21
ns2.hkirc.net.hk.	172800	IN	AAAA	2001:dca:1000::cb77:5713
sec3.apnic.net.		172800	IN	AAAA	2001:dc0:1:0:4777::140

;; Query time: 126 msec
;; SERVER: 2001:dc3::35#53(m.root-servers.net)
;; WHEN: Mon May 21 11:41:13 2012
;; MSG SIZE  rcvd: 487

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1125
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 6, ADDITIONAL: 6

;; QUESTION SECTION:
;ied.edu.hk.			IN	SOA

;; AUTHORITY SECTION:
edu.hk.			604800	IN	NS	NS2.HKIRC.NET.hk.
edu.hk.			604800	IN	NS	HK-NS.PCH.NET.
edu.hk.			604800	IN	NS	Z.HKIRC.NET.hk.
edu.hk.			604800	IN	NS	B.DNS.TW.
edu.hk.			604800	IN	NS	NS2.CUHK.edu.hk.
edu.hk.			604800	IN	NS	NS1.HKIRC.NET.hk.

;; ADDITIONAL SECTION:
Z.HKIRC.NET.hk.		604800	IN	A	194.146.106.70
Z.HKIRC.NET.hk.		604800	IN	AAAA	2001:67c:1010:17::53
NS1.HKIRC.NET.hk.	604800	IN	A	203.119.2.18
NS2.CUHK.edu.hk.	604800	IN	A	137.189.6.21
NS2.HKIRC.NET.hk.	604800	IN	A	203.119.87.19
NS2.HKIRC.NET.hk.	604800	IN	AAAA	2001:dca:1000::cb77:5713

;; Query time: 211 msec
;; SERVER: 2607:f140:ffff:fffe::3#53(adns1.berkeley.edu)
;; WHEN: Mon May 21 11:41:13 2012
;; MSG SIZE  rcvd: 282

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 499
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 5, ADDITIONAL: 5

;; QUESTION SECTION:
;ied.edu.hk.			IN	SOA

;; AUTHORITY SECTION:
ied.edu.hk.		28800	IN	NS	TC-EDNS1.ied.edu.hk.
ied.edu.hk.		28800	IN	NS	EDNS1.ied.edu.hk.
ied.edu.hk.		28800	IN	NS	TC-EDNS2.ied.edu.hk.
ied.edu.hk.		28800	IN	NS	ITS1.ied.edu.hk.
ied.edu.hk.		28800	IN	NS	EDNS2.ied.edu.hk.

;; ADDITIONAL SECTION:
ITS1.ied.edu.hk.	28800	IN	A	202.45.32.1
EDNS1.ied.edu.hk.	28800	IN	A	202.45.32.3
EDNS2.ied.edu.hk.	28800	IN	A	202.45.32.230
TC-EDNS1.ied.edu.hk.	28800	IN	A	202.45.39.87
TC-EDNS2.ied.edu.hk.	28800	IN	A	202.45.39.75

;; Query time: 146 msec
;; SERVER: 2001:dca:1000::cb77:5713#53(NS2.HKIRC.NET.hk)
;; WHEN: Mon May 21 11:41:16 2012
;; MSG SIZE  rcvd: 213

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 285
;; flags: qr aa; QUERY: 1, ANSWER: 1, AUTHORITY: 5, ADDITIONAL: 5

;; QUESTION SECTION:
;ied.edu.hk.			IN	SOA

;; ANSWER SECTION:
ied.edu.hk.		86400	IN	SOA	edns1.ied.edu.hk. ffong.ied.edu.hk. 1205180914 86400 10800 604800 86400

;; AUTHORITY SECTION:
ied.edu.hk.		86400	IN	NS	edns1.ied.edu.hk.
ied.edu.hk.		86400	IN	NS	tc-edns1.ied.edu.hk.
ied.edu.hk.		86400	IN	NS	edns2.ied.edu.hk.
ied.edu.hk.		86400	IN	NS	tc-edns2.ied.edu.hk.
ied.edu.hk.		86400	IN	NS	its1.ied.edu.hk.

;; ADDITIONAL SECTION:
its1.ied.edu.hk.	86400	IN	A	202.45.32.1
edns1.ied.edu.hk.	86400	IN	A	202.45.32.3
edns2.ied.edu.hk.	86400	IN	A	202.45.32.230
tc-edns1.ied.edu.hk.	86400	IN	A	202.45.39.87
tc-edns2.ied.edu.hk.	86400	IN	A	202.45.39.75

;; Query time: 115 msec
;; SERVER: 202.45.39.75#53(TC-EDNS2.ied.edu.hk)
;; WHEN: Mon May 21 11:41:16 2012
;; MSG SIZE  rcvd: 255

HTTP

Looking for CNAME of www.ied.edu.hk
Checking if there is a AAAA for www.ied.edu.hk ... FAILED.


; <<>> DiG 9.4.1-P1 <<>> www.ied.edu.hk aaaa
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1855
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;www.ied.edu.hk.			IN	AAAA

;; AUTHORITY SECTION:
ied.edu.hk.		10800	IN	SOA	edns1.ied.edu.hk. ffong.ied.edu.hk. 1205180914 86400 10800 604800 86400

;; Query time: 4 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Mon May 21 11:41:17 2012
;; MSG SIZE  rcvd: 80

Checking other options ... failed too.

SMTP

MX 10 esa3.hkied.iphmx.com
Looking for AAAA on esa3.hkied.iphmx.com
MX 10 esa1.hkied.iphmx.com
Looking for AAAA on esa1.hkied.iphmx.com

DNS

Looking for AAAA of NS edns2.ied.edu.hk
No AAAA record for edns2.ied.edu.hk
Looking for AAAA of NS its1.ied.edu.hk
No AAAA record for its1.ied.edu.hk
Looking for AAAA of NS tc-edns1.ied.edu.hk
No AAAA record for tc-edns1.ied.edu.hk
Looking for AAAA of NS edns1.ied.edu.hk
No AAAA record for edns1.ied.edu.hk
Looking for AAAA of NS tc-edns2.ied.edu.hk
No AAAA record for tc-edns2.ied.edu.hk

NTP

Looking for an A record for ntp.ied.edu.hk
Looking for an A record for clock.ied.edu.hk
Looking for an A record for time.ied.edu.hk
Looking for an A record for chime.ied.edu.hk

XMPP

Looking for a SRV record for _xmpp-client._tcp.ied.edu.hk
Looking for a SRV record for _xmpp-server._tcp.ied.edu.hk

Last Updated: Mon May 21 02:11:19 2012 UTC