[geeks] simple DNS / nslookup question

[John Francini]

If you run nslookup interactively, you can give it the "set  
querytype=any" and "debug" commands and get a whole lot more info:

% nslookup
 > debug
 > set querytype=any
 > yahoo.com
Server:         68.87.71.226
Address:        68.87.71.226#53

------------
     QUESTIONS:
         yahoo.com, type = ANY, class = IN
     ANSWERS:
     ->  yahoo.com
         internet address = 216.109.112.135
     ->  yahoo.com
         internet address = 66.94.234.13
     ->  yahoo.com
         nameserver = ns5.yahoo.com.
     ->  yahoo.com
         nameserver = ns6.yahoo.com.
     ->  yahoo.com
         nameserver = ns8.yahoo.com.
     ->  yahoo.com
         nameserver = ns2.yahoo.com.
     ->  yahoo.com
         nameserver = ns1.yahoo.com.
     ->  yahoo.com
         nameserver = ns3.yahoo.com.
     ->  yahoo.com
         nameserver = ns4.yahoo.com.
     ->  yahoo.com
         mail exchanger = 1 f.mx.mail.yahoo.com.
     ->  yahoo.com
         mail exchanger = 1 g.mx.mail.yahoo.com.
     ->  yahoo.com
         mail exchanger = 1 a.mx.mail.yahoo.com.
     ->  yahoo.com
         mail exchanger = 1 b.mx.mail.yahoo.com.
     ->  yahoo.com
         mail exchanger = 1 c.mx.mail.yahoo.com.
     ->  yahoo.com
         mail exchanger = 1 d.mx.mail.yahoo.com.
     ->  yahoo.com
         mail exchanger = 1 e.mx.mail.yahoo.com.
     AUTHORITY RECORDS:
     ADDITIONAL RECORDS:
     ->  ns6.yahoo.com
         internet address = 202.43.223.170
     ->  ns8.yahoo.com
         internet address = 202.165.104.22
     ->  ns2.yahoo.com
         internet address = 68.142.255.16
     ->  ns1.yahoo.com
         internet address = 66.218.71.63
     ->  ns3.yahoo.com
         internet address = 217.12.4.104
     ->  ns4.yahoo.com
         internet address = 68.142.196.63
     ->  ns5.yahoo.com
         internet address = 216.109.116.17
     ->  g.mx.mail.yahoo.com
         internet address = 206.190.53.191
     ->  g.mx.mail.yahoo.com
         internet address = 209.191.88.239
     ->  a.mx.mail.yahoo.com
         internet address = 209.191.118.103
     ->  b.mx.mail.yahoo.com
         internet address = 66.196.97.250
     ->  c.mx.mail.yahoo.com
         internet address = 68.142.237.182
------------
Non-authoritative answer:
Name:   yahoo.com
Address: 216.109.112.135
Name:   yahoo.com
Address: 66.94.234.13
yahoo.com       nameserver = ns5.yahoo.com.
yahoo.com       nameserver = ns6.yahoo.com.
yahoo.com       nameserver = ns8.yahoo.com.
yahoo.com       nameserver = ns2.yahoo.com.
yahoo.com       nameserver = ns1.yahoo.com.
yahoo.com       nameserver = ns3.yahoo.com.
yahoo.com       nameserver = ns4.yahoo.com.
yahoo.com       mail exchanger = 1 f.mx.mail.yahoo.com.
yahoo.com       mail exchanger = 1 g.mx.mail.yahoo.com.
yahoo.com       mail exchanger = 1 a.mx.mail.yahoo.com.
yahoo.com       mail exchanger = 1 b.mx.mail.yahoo.com.
yahoo.com       mail exchanger = 1 c.mx.mail.yahoo.com.
yahoo.com       mail exchanger = 1 d.mx.mail.yahoo.com.
yahoo.com       mail exchanger = 1 e.mx.mail.yahoo.com.

Authoritative answers can be found from:
ns6.yahoo.com   internet address = 202.43.223.170
ns8.yahoo.com   internet address = 202.165.104.22
ns2.yahoo.com   internet address = 68.142.255.16
ns1.yahoo.com   internet address = 66.218.71.63
ns3.yahoo.com   internet address = 217.12.4.104
ns4.yahoo.com   internet address = 68.142.196.63
ns5.yahoo.com   internet address = 216.109.116.17
g.mx.mail.yahoo.com     internet address = 206.190.53.191
g.mx.mail.yahoo.com     internet address = 209.191.88.239
a.mx.mail.yahoo.com     internet address = 209.191.118.103
b.mx.mail.yahoo.com     internet address = 66.196.97.250
c.mx.mail.yahoo.com     internet address = 68.142.237.182
 >

Hope this helps!

John


On 2 Dec 2007, at 0:43, kevin marshall wrote:

> I'm trying to help my mother with an email server/MX record issue and
> have run across a question i've had for a while, i just never really
> needed an answer until now.
>
> If you run nslookup as such, against a domain, without a host name
> specified:
>
> #nslookup yahoo.com
>
> You will receive a response.  This does not work for all domains
> however.  What type of record is this response (domain queries  
> lacking a
> specific host name) and how do i set up something like this in bind?
>
> Of course i would get an MX record if i set type=mx and queried just a
> domain, but i'm talking about domain only queries with no specific  
> type set.
>
> Thanks,
> /KRM
>
> FYI: Her actual problem is getting her email server (nbww.com) to send
> mail to pjgeng.org, but the DNS for pjgeng.org is screwed (no MX  
> record).
> _______________________________________________
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