USNS issue

[Abhijit Pandey]

Hi Michael,

Thanks for your mail. Couple more question.
I don't have a DNS server running locally.

Is UDNS not maintaing the resolver cache on my PC?
Does your UDNS also depends on BIND-Utils ?


1) Here is the output when I rerun the Query.
          I see the additional section and Answer section getting flipped.

*dnsget: unable to lookup A record for www.yahoo.com: valid domain but no
data of requested type*

[apandey at localhost udns-0.0.9]$ ./dnsget -vv www.yahoo.com
;; trying www.yahoo.com.
;; sending 42 bytes query to 192.168.15.1 port 53
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 30366, size: 42
;; flags: rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; QUERY SECTION (1):
;www.yahoo.com. IN A

;; ADDITIONAL section (1):
;EDNS0 OPT record (UDPsize: 4096): 0 bytes

;; received 58 bytes response from 192.168.15.1 port 53
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 30366, size: 58
;; flags: qr rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; QUERY SECTION (1):
;www.yahoo.com. IN A

;; ANSWER section (1):
;EDNS0 OPT record (UDPsize: 4096): 0 bytes

;; ADDITIONAL section (1):
www.yahoo.com. 10000 IN A 209.131.36.158

*dnsget: unable to lookup A record for www.yahoo.com: valid domain but no
data of requested type
*


2)
Here is the output query when I provide the same arguments 3 times in the
command line with -vv mode.

[apandey at localhost udns-0.0.9]$ ./dnsget -vv www.yahoo.com www.yahoo.com
www.yahoo.com
;; trying www.yahoo.com.
;; sending 42 bytes query to 192.168.15.1 port 53
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40089, size: 42
;; flags: rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; QUERY SECTION (1):
;www.yahoo.com. IN A

;; ADDITIONAL section (1):
;EDNS0 OPT record (UDPsize: 4096): 0 bytes

;; trying www.yahoo.com.
;; sending 42 bytes query to 192.168.15.1 port 53
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40088, size: 42
;; flags: rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; QUERY SECTION (1):
;www.yahoo.com. IN A

;; ADDITIONAL section (1):
;EDNS0 OPT record (UDPsize: 4096): 0 bytes

;; trying www.yahoo.com.
;; sending 42 bytes query to 192.168.15.1 port 53
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40087, size: 42
;; flags: rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; QUERY SECTION (1):
;www.yahoo.com. IN A

;; ADDITIONAL section (1):
;EDNS0 OPT record (UDPsize: 4096): 0 bytes

;; received 96 bytes response from 192.168.15.1 port 53
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40089, size: 96
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1

;; QUERY SECTION (1):
;www.yahoo.com. IN A

;; ANSWER section (2):
www.yahoo.com. 110 IN CNAME www.yahoo-ht3.akadns.net.
www.yahoo-ht3.akadns.net. 53 IN A 209.131.36.158

;; ADDITIONAL section (1):
;EDNS0 OPT record (UDPsize: 4000): 0 bytes

;; received 96 bytes response from 192.168.15.1 port 53
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40088, size: 96
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1

;; QUERY SECTION (1):
;www.yahoo.com. IN A

;; ANSWER section (2):
www.yahoo.com. 289 IN CNAME www.yahoo-ht3.akadns.net.
www.yahoo-ht3.akadns.net. 57 IN A 209.131.36.158

;; ADDITIONAL section (1):
;EDNS0 OPT record (UDPsize: 4000): 0 bytes

;; received 96 bytes response from 192.168.15.1 port 53
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40087, size: 96
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1

;; QUERY SECTION (1):
;www.yahoo.com. IN A

;; ANSWER section (2):
www.yahoo.com. 289 IN CNAME www.yahoo-ht3.akadns.net.
www.yahoo-ht3.akadns.net. 57 IN A 209.131.36.158

;; ADDITIONAL section (1):
;EDNS0 OPT record (UDPsize: 4000): 0 bytes




On Sun, Feb 1, 2009 at 2:28 AM, Michael Tokarev
<mjt+udns at corpit.ru<mjt%2Budns at corpit.ru>>
wrote:
> Abhijit Pandey wrote:
>> Hi Michael,
>>
>> Thanks for writing UDNS.
>>
>> I had a quick question, I am trying to run dnsget with a "hostname."
>> If I repeat the same query I get this error
>> unable to lookup A record for "hostname": valid domain but no data of
>> requested type
>>
>> Let me know how I should fix this.
>
> Run it in verbose mode (add -v command-line switch) and see which
> flags are present in answer in first and second cases (I assume
> that the first time it correctly returns "domain does not exist").
>
> My guess is your resolver cache is at fault here.  But impossible
> to say w/o the complete reply as seen by dnsget.
>
> /mjt
>
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