I want to filter out Non-authoritative answer Address information if it exists so that in response I would get only "127.0.5.0" and nothing when there is nothing returned. Here is example:
user@machine:~$ nslookup honeypotkey.71.78.249.66.dnsbl.httpbl.org
Server: 109.74.192.20
Address: 109.74.192.20#53
Non-authoritative answer:
Name: ryjonpjinfae.71.78.249.66.dnsbl.httpbl.org
Address: 127.0.5.0
Regards, Edijs
If I understand your question you want only answers that are authoritative? If so this isn't directly possible with a single nslookup and/or dig command (at least not to my knowledge - unless you know which nameserver is authoritative for your queried lookup).
Given this you'll have to perform 3 look ups to get an authoritative answer.
% nslookup -type=soa honeypotkey.71.78.249.66.dnsbl.httpbl.org.
Server: 192.168.1.5
Address: 192.168.1.5#53
Non-authoritative answer:
*** Can't find honeypotkey.71.78.249.66.dnsbl.httpbl.org.: No answer
Authoritative answers can be found from:
dnsbl.httpbl.org
origin = dnsbl.httpbl.org
mail addr = dnsadmin.projecthoneypot.org
serial = 1359954681
refresh = 7200
retry = 7200
expire = 604800
minimum = 3600
% nslookup -type=ns dnsbl.httpbl.org
Server: 192.168.1.5
Address: 192.168.1.5#53
Non-authoritative answer:
dnsbl.httpbl.org nameserver = ns3.httpbl.org.
dnsbl.httpbl.org nameserver = ns2.httpbl.org.
dnsbl.httpbl.org nameserver = ns1.httpbl.org.
Authoritative answers can be found from:
ns3.httpbl.org internet address = 81.17.242.92
ns2.httpbl.org internet address = 66.114.104.118
ns1.httpbl.org internet address = 209.124.55.46
% nslookup honeypotkey.71.78.249.66.dnsbl.httpbl.org. ns1.httpbl.org
Server: ns1.httpbl.org
Address: 209.124.55.46#53
Name: honeypotkey.71.78.249.66.dnsbl.httpbl.org
Address: 127.0.5.0
Let me know if this is what you're after. If not I can adjust this answer if needed.
