There are various ways to query whether a domain is available, and domains "in limbo" can yield different results across different methods. GoDaddy and other big registrars most often query registries directly via proprietary means. These are most certainly fallible, and that is not the fault of GoDaddy.
For example, a relatively reliable means of determining the existence of a domain is DNS. dig is my tool of choice, and
kloth.net happens to provide online access to dig, along with a bunch of other cool Linux toys. Let's see what happens when I query an obviously non-existent domain with dig:
Input:
Note: the trailing dot on the next line is not a typo; fully qualified domain names (FQDNs) always end in a dot.
Domain: vnuerkgnumrnfujencj.com.
Server: localhost
Query: SOA (start of authority)
Output:
; <<>> DiG 9.7.3 <<>> @localhost vnuerkgnumrnfujencj.com SOA
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 42699
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
;; QUESTION SECTION:
;vnuerkgnumrnfujencj.com. IN SOA
;; AUTHORITY SECTION:
com. 900 IN SOA a.gtld-servers.net. nstld.verisign-grs.com. 1393073555 1800 900 604800 86400
;; Query time: 13 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Sat Feb 22 13:52:55 2014
;; MSG SIZE rcvd: 114
The most important part is in red: NXDOMAIN. That means "non-existent domain": it's
most likely available for registration.
Then we have the SOA response in green and blue. The green text is important because it shows "com." instead of "vnuerkgnumrnfujencj.com."--since com. exists, its SOA record will show which nameserver is authoritative for vnuerkgnumrnfujencj.com, seeing how vnuerkgnumrnfujencj.com lacks its own SOA record. This is another sign that the domain is available: all functioning second level domains need their own SOA records, or they won't resolve.
The blue text shows that VeriSign's nameservers are authoritative. Even if the domain existed and had its own SOA record, this value would be a good indication that the domain was in some sort of limbo, as the registry (not registrar) currently has control over the domain. Such a domain could theoretically become available to the public at any moment.
If you had queried this domains via DNS, you probably would have found that they were already taken, even if they didn't resolve to IPv4 addresses--that is, they could have been lacking A records.
Another method is WHOIS. WHOIS is an actual protocol, like DNS; it's separate from the web (HTTP), though most people only know how to access it via websites. There are programs that can query WHOIS servers directly; kloth.net has a web wrapper around the Linux whois program, but it doesn't let you specify a custom server to query, so it's not that great for new gTLDs and some ccTLDs. I'm going to use the actual GNU whois program on Linux to run an example query, since I'm not satisfied with
kloth.net's solution, but you should be able to achieve similar results there.
Input:
Code:
whois vnuerkgnumrnfujencj.com
Output:
Truncated for brevity.
Code:
Whois Server Version 2.0
Domain names in the .com and .net domains can now be registered
with many different competing registrars. Go to http://www.internic.net
for detailed information.
No match for partial "VNUERKGNUMRNFUJENCJ.COM".
>>> Last update of whois database: Sat, 22 Feb 2014 13:18:12 UTC <<<
Tangent:
In reality, TLDs aren't any different from second level domains. Though ICANN forbids it, a TLD can have A records and resolve to an IP address, so there could be a website, at, say,
http://com/ or
http://net/. The TLD/SLD line is drawn by ICANN, not by the DNS protocol--or any other widespread technical protocol, for that matter. Watch, I can run a WHOIS query on com:
Code:
paul@vm:~$ whois -h whois.iana.org com
% IANA WHOIS server
% for more information on IANA, visit http://www.iana.org
% This query returned 1 object
domain: COM
organisation: VeriSign Global Registry Services
address: 12061 Bluemont Way
address: Reston Virginia 20190
address: United States
contact: administrative
name: Registry Customer Service
organisation: VeriSign Global Registry Services
address: 12061 Bluemont Way
address: Reston Virginia 20190
address: United States
phone: +1 703 925-6999
fax-no: +1 703 948 3978
e-mail: [email protected]
contact: technical
name: Registry Customer Service
organisation: VeriSign Global Registry Services
address: 12061 Bluemont Way
address: Reston Virginia 20190
address: United States
phone: +1 703 925-6999
fax-no: +1 703 948 3978
e-mail: [email protected]
nserver: A.GTLD-SERVERS.NET 192.5.6.30 2001:503:a83e:0:0:0:2:30
nserver: B.GTLD-SERVERS.NET 192.33.14.30 2001:503:231d:0:0:0:2:30
nserver: C.GTLD-SERVERS.NET 192.26.92.30
nserver: D.GTLD-SERVERS.NET 192.31.80.30
nserver: E.GTLD-SERVERS.NET 192.12.94.30
nserver: F.GTLD-SERVERS.NET 192.35.51.30
nserver: G.GTLD-SERVERS.NET 192.42.93.30
nserver: H.GTLD-SERVERS.NET 192.54.112.30
nserver: I.GTLD-SERVERS.NET 192.43.172.30
nserver: J.GTLD-SERVERS.NET 192.48.79.30
nserver: K.GTLD-SERVERS.NET 192.52.178.30
nserver: L.GTLD-SERVERS.NET 192.41.162.30
nserver: M.GTLD-SERVERS.NET 192.55.83.30
ds-rdata: 30909 8 2 E2D3C916F6DEEAC73294E8268FB5885044A833FC5459588F4A9184CFC41A5766
whois: whois.verisign-grs.com
status: ACTIVE
remarks: Registration information: http://www.verisign-grs.com
created: 1985-01-01
changed: 2012-02-15
source: IANA