Clarification on question and the answer section uppercase lower case mis match

[Kevin Oberman]

On Tue, Apr 10, 2012 at 2:56 AM, rams <bramesh80 at gmail.com> wrote:
> Hi,
> When i queried domain with capital letters , In answer section domain name
> is displaying small letters. Is it expected? any RFC for this?
>
> dig @localhost D.ashwintrail.com
>
>
> ; <<>> DiG 9.2.4 <<>> @localhost D.ashwintrail.com
> ; (1 server found)
> ;; global options: printcmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 23469
> ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 0
>
> ;; QUESTION SECTION:
> ;D.ashwintrail.com. IN A
>
> ;; ANSWER SECTION:
> d.ashwintrail.com. 86400 IN A 2.3.4.5
>
> ;; AUTHORITY SECTION:
> ashwintrail.com. 86400 IN NS ramesh.com.
> ashwintrail.com. 86400 IN NS ramesh1.com.
>
> ;; Query time: 0 msec
> ;; SERVER: #53
> ;; WHEN: Tue Apr 10 02:19:00 2012
> ;; MSG SIZE rcvd: 105
>
> Thanks & Regards,
> Ramesh

Since the very first DNS RFCs, DNS is case preserving but not case
sensitive. That means that a query with differences in case will
return a match with the appropriate data, just the same as when case
matches, but will return the case of the authoritative record.

See RFC1034 3.1 for a general description or RFC1035, section 2.3.3 for detail.
-- 
R. Kevin Oberman, Network Engineer
E-mail: kob6558 at gmail.com