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I'm trying to configure a DNS server for domain.com. I want to configure a wildcard DNS record to resolve any-subdomain.domain.com to a single IP address (172.16.1.3). In my DNS server I have the following records in my forward zone:

DNS Records

This somewhat works, except that when I run nslookup www.domain.com I get this response:

Server: winsrv.domain.com
Address: 172.16.1.2

Name: www.domain.com.domain.com
Address: 172.16.1.3

I believe the DNS server is thinking that the entire www.domain.com string is a subdomain of domain.com.

How do I get the DNS server to return the correct line: Name: www.domain.com

Brack
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  • Is `domain.com` in this example an Active Directory domain as well? And if so, is this DNS server an AD DNS server? – MDMarra Sep 13 '13 at 19:25
  • Nope, no AD in use. Just a fresh Windows Server 2012 with updates and DNS installed. – Brack Sep 13 '13 at 19:32

1 Answers1

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Here's what I suspect is happening but can't prove it on my own systems since I don't want to stick a wildcard record on my DNS servers.

This somewhat works, except that when I run nslookup www.domain.com I get this response:

Server: winsrv.domain.com
Address: 172.16.1.2

Name: www.domain.com.domain.com
Address: 172.16.1.3

This is because your nslookup query is technically an unqualified name.

You can test this by doing an nslookup www.domain.com. (note the trailing period/dot at the end that "qualifies" it) and see if the return is valid now.

EDIT: yeah this seams to be the case...because your wildcard entry is invalidating the normal NXDOMAIN response nslookup normally returns in this case. Since nslookup always appends the suffix if the lookup doesn't have the trailing period.

For instance, here's one on my computer:

> set debug=true
> www.yahoo.com
Server:  dc1.mdmarra.local
Address:  10.10.10.10

------------
Got answer:
    HEADER:
        opcode = QUERY, id = 2, rcode = NXDOMAIN
        header flags:  response, auth. answer, want recursion, recursion avail.
        questions = 1,  answers = 0,  authority records = 1,  additional = 0

    QUESTIONS:
        www.yahoo.com.mdmarra.local, type = A, class = IN
    AUTHORITY RECORDS:

Notice how it returned NXDOMAIN for www.yahoo.com.mdmarra.local. It will then go on to query just www.yahoo.com using forwarders. Since you have the wildcard entry it thinks your query is valid based on the wildcard.

TheCleaner
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