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If you have many sub-domain names like, etc, you can solve these through server-side scripting or other means by using a wildcard A record for * in your DNS.

How can I determine whether a wildcard domain is configured for any given domain name? Using gives a lot of information, but doesn't reveal this. If I need to use commandline tools: I use Windows. One such example that uses a wildcard domain DNS, I think, is

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up vote 13 down vote accepted

You can literally query "*" and find out if there is a wildcard, but it is impossible to tell the difference between these two zones:  IN A
*    IN A


*    IN A

i.e., you can't find out whether you're being answered by a wildcard for a given query, only that a wildcard exists.

I haven't found any Web-accessible looking glasses that support it yet, as they seem to think it's invalid input, but raw dig (or even nslookup on Windows) works like a charm:

c:\Some\User> nslookup
> *
Server:  Wireless_Broadband_Router.home

Non-authoritative answer:
Name:    *

Or with dig:

# dig +short '*'
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+1: for valuable insight. Could you elaborate and also explain me how I could do such a query, or what online network/dns tools support such query (tried, but didn't find it myself)? – Abel Jul 15 '10 at 13:51
Using nslookup, I get a list of aliases, for instance, * returns an alias with the same name. Using returns an alias with the same name. Both receive an answer of Name: When I use *, no aliases are given, but the answer is Name: * Do I understand this correctly that blogspot uses wildcard aliases (CNAME) and undermyhat uses wildcard A records? – Abel Jul 15 '10 at 14:12
Using dig, you can see more of the return code. I'll put it in an answer so I get formatting, but mark this one as the answer, not mine :) – Bill Weiss Jul 15 '10 at 15:06

In response to BMDan's good answer:

houdini@linode:~/ > dig '*' +noall +answer
*         3352    IN      CNAME  52      IN      A
houdini@linode:~/ > ^^
dig '*' +noall +answer
*       14400   IN      A
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Thanks for answering my latest questions in a separate post. Seems like dig can indeed get quite a bit more. Hmm, CygWin? I'll google some Windows alternatives and meanwhile use my Linux vm. – Abel Jul 15 '10 at 15:34

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