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NSLOOKUP

advanced DNS queries.
1.

Open A Command Prompt

 
 
   
 
3.

Start Nslookup

Type:

nslookup

Press Enter on the keyboard.

 
 
4.

Check What Options Are Available With Help or ?

Type:

help

or, type:

?

Press Enter on the keyboard.

 
 
5.

To Check Mail or MX Records

To Check DNS Mail or MX Records for a specific domain, it is easiest to first set the parameters, then to make the actual query, in two separate steps. (More advanced queries can have more than two parameters set across several commands.) To query for MX Records, use the SET TYPE option. So, to check the MX Records for the domain, yahoo.com, type:

set type=MX

Press ENTER on the keyboard. This tells nslookup that any subsequent queries are to return MX record information. This is not just a one time setting, as all queries for this nslookup session will remain for the type set, until the type is changed.

To finish the query for MX Records for the yahoo.com domain, next type:

yahoo.com

Press ENTER on the keyboard.

 
 
6.

To Check All or ANY Records

To check all or ANY DNS Records for a specific domain, it is easiest to first set the parameters, then to make the actual query, in two separate steps. This is similar to the method mentioned above, in "To Check Mail or MX Records." To check for ANY Records for the domain, yahoo.com, type:

set type=ANY

Press ENTER on the keyboard. Then type:

yahoo.com

Press ENTER on the keyboard.

 
7.

To Change The Default DNS Server

Something which is very much misunderstood by most entities is that, at times, propagation can be bypassed. This is helpful to verify DNS changes without having to wait for propagation. One method for bypassing propagation is to change the nslookup session's default DNS server to the authoritative DNS server of the domain which is to be queried. This does not always work as expected, for various reasons, but it is usually worthwhile to try.

In previous examples, the authoritative name server, or DNS server, for the domain yahoo.com has been ns1.onr.com. So, to change the default DNS server to this name server, type:

server ns1.xyz.com

Press ENTER on the keyboard.

 
8.

To Receive Verbose Feedback - Debug

To receive verbose or debugging information for each query, use the SET DEBUG option. To do this, type:

set debug

Press ENTER on the keyboard.

Now that the debug option has been set, subsequent queries will display more information about what queries and communication is actually taking place. To see an example of the debugging information, type:

yahoo.com

Press ENTER on the keyboard. You should see more output on the screen which gives more details regarding the query.

To see even more verbose output, use the SET D2 option. To do this, type:

set d2

Press ENTER on the keyboard. Subsequent queries will yield a lot more output.

 

 

 

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Revised: 04/12/13