Where can I find the most up-to-date information on my domain's name servers?

Question

I just switched registrars for a bunch of domains and the new registrar didn't copy over my existing name servers. Now all my pages appear as "parked" domains when you visit them.

I've gone in and updated all of the name servers with my new registrar, back to their old values, but I want to make sure those changes have taken affect. I know I need to wait for ISPs to update their caches once the name servers change back, but I was wondering if there was some central ICANN database I could check to make sure they were updated properly.

Thanks!

Answer 1

Basically, what happens when you change your nameservers at your registrar is that they submit the changes to the registry, which keeps a WHOIS database as well as an authoritative nameserver for that TLD. So, in theory, the AS for your TLD is the first to know about the changed nameservers via updated NS records. That is where the DNS propagation begins.

IP tools or a direct DNS lookup via command line tools like nslookup or dig are the best way to see what the nameservers are set as. However, to see if the nameservers have been set properly before the DNS info fully propagates, you need to use the authoritative nameservers for your TLD. Otherwise, these tools will use the default local DNS server, which is likely a DNS cache.

So to do what you want manually, you have to:

1. Find the authoritative nameservers for your TLD

The root zone file lists the AS of all TLDs; however, you need to find the ones for your TLD. You can find this out with a simple dig command:

$ dig +short NS com
j.gtld-servers.net.
b.gtld-servers.net.
d.gtld-servers.net.
[...]
e.gtld-servers.net.
k.gtld-servers.net.
l.gtld-servers.net.

2. Then look up the NS records for your domain via one of them:

You can do this with dig:

$ dig ns example.com @j.gtld-servers.net

; <<>> DiG 9.6-ESV-R4 <<>> NS example.com @j.gtld-servers.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27086
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 4
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;example.com.                   IN      NS

;; AUTHORITY SECTION:
example.com.            172800  IN      NS      a.iana-servers.net.
example.com.            172800  IN      NS      b.iana-servers.net.

;; ADDITIONAL SECTION:
[...]

;; Query time: 170 msec
;; SERVER: 192.48.79.30#53(192.48.79.30)
;; WHEN: Fri Feb 24 11:39:21 2012
;; MSG SIZE  rcvd: 165

or nslookup:

C:\>nslookup example.com j.gtld-servers.net
(root)  nameserver = e.root-servers.net
[...]
(root)  nameserver = d.root-servers.net
Server:  UnKnown
Address:  192.48.79.30

Name:    example.com
Served by:
- a.iana-servers.net
      199.43.132.53
      2001:500:8c::53
      example.com
- b.iana-servers.net
      199.43.133.53
      2001:500:8d::53
      example.com

Or just do it the easy way

Alternatively, you could have simply used the dig +trace command to do a DNS trace. However, this may not work with your local DNS server, so it's best to do it via a public DNS server like Google's:

$  dig example.com +trace @8.8.8.8

; <<>> DiG 9.6-ESV-R4 <<>> example.com +trace @8.8.8.8
;; global options: +cmd
.                       14412   IN      NS      e.root-servers.net.
[...]
;; Received 228 bytes from 8.8.8.8#53(8.8.8.8) in 28 ms

com.                    172800  IN      NS      j.gtld-servers.net.
[...]
com.                    172800  IN      NS      b.gtld-servers.net.
;; Received 489 bytes from 192.228.79.201#53(b.root-servers.net) in 16 ms

example.com.            172800  IN      NS      a.iana-servers.net.
example.com.            172800  IN      NS      b.iana-servers.net.
;; Received 165 bytes from 192.52.178.30#53(k.gtld-servers.net) in 156 ms

example.com.            172800  IN      A       192.0.43.10
example.com.            172800  IN      NS      b.iana-servers.net.
example.com.            172800  IN      NS      a.iana-servers.net.
;; Received 93 bytes from 2001:500:8c::53#53(a.iana-servers.net) in 12 ms

As you can see, this automatically fetches the NS records from one of the ASes but also lists all the ASes for your TLD so you can do a manual NS lookup on each one individually as shown earlier if you want.

Answer 2

There isn't a database beyond the whois - which won't help you as it isn't updated frequently enough.

Try www.iptools.com, they have a wide variety of tools for checking your domain's DNS settings and more besides.

I would also reccommend mxtoolbox.com for checking mx records and email blacklists.

Answer 3

I like to use http://www.whatsmydns.net to check the propagation of DNS settings it checks across about 20 different DNS servers

Answer 4

As I discovered, each top level domain (TLD) has a single, central registry that maintains the list of domain names registered under that TLD, and their corresponding name servers.

For .com .net .edu .cc .tv .jobs and .name TLDs, the central registry is Verisign. You can perform a whois lookup on their list by visiting:

http://www.verisigninc.com/en_US/products-and-services/domain-name-services/whois/index.xhtml

While there are many great tools listed in other answers, the Verisign list is the most up-to-date and authoritative. Thanks to all who answered!