[dns-operations] A lot of CNAME queries for domain ?

Mohamed Lrhazi ml623 at georgetown.edu
Thu Jul 5 17:17:28 UTC 2012

Yeah... I did read somewhere recently that some SMTP RFC does say the mail
server should query for the CNAME record, but only if MX record was not

I still don't understand why I see so many such queries... This is bigger
issue because I just found out my DNS server is generating a malformed
packet, as a response to these specific queries...


On Thu, Jul 5, 2012 at 12:43 PM, Simon Munton <Simon.Munton at communitydns.net
> wrote:

> That sounds odd to me as CNAME records are not normally ever specifically
> queried (asked) for.
> Where they exist, they are given as reply to a query for any RR type, but
> the CNAME itself is then followed by the resolver until an answer is
> achieved.
> e.g.
> authority => www IN CNAME web1
> query     => www/IN/A
> reply     => www IN CNAME web1
> You don't actually ask for the CNAME, in that respect its similar to a
> wildcard. In my little example, we asked for an "A" records, but were given
> the CNAME.
> On 05/07/2012 15:32, Mohamed Lrhazi wrote:
>> Hello all,
>> If this is not an appropriate question for the list, please accept
>> my apologies and please suggest a better one.
>> I just started administering DNS for my organisation and I notice in the
>> query logs a lot of queries of type CNAME for our domain, say,
>> example.com <http://example.com>
>> We do not have such a record and so these queries get an empty answer.
>> I am just curious what applications out there would be generating such
>> queries... Please note that we do have an MX record for the domain and
>> also an A record.
>> Thanks a lot,
>> Mohamed.
>> ______________________________**_________________
>> dns-operations mailing list
>> dns-operations at lists.dns-oarc.**net <dns-operations at lists.dns-oarc.net>
>> https://lists.dns-oarc.net/**mailman/listinfo/dns-**operations<https://lists.dns-oarc.net/mailman/listinfo/dns-operations>
>> dns-jobs mailing list
>> https://lists.dns-oarc.net/**mailman/listinfo/dns-jobs<https://lists.dns-oarc.net/mailman/listinfo/dns-jobs>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.dns-oarc.net/pipermail/dns-operations/attachments/20120705/ac692d86/attachment.html>

More information about the dns-operations mailing list