doubt regarding Caching server Implementation....

[Sanjib Das]

Hi
I have setup a local domain my.domain. & it consists of two machines...
I configured one of them as primary server for my domain & another one
as caching server .For both these servers I'm using BIND-9.2.4 package
whenever I send query (using 'dig' command).....
from the second machine (machine where the caching server is running 
locally) first it looks into its own cache....if its available it sends 
from there 
itself... otherwise sends it to the primary server...now whenever it 
(caching 
server)sends to primary server.

Say I sent a query dig A.example.com. A  .... say the caching server
does not have the information in its own cache...so it sends to the 
primary server...now if I run tcpdump...I find that the caching server
not only sends the query for qtypw=A...it sends the same for qtype=NS, 
qtype=PTR...but in my query I only asked for qtype=A .....
I donno exactly why it sends two more queries, which I dint send.....

Please share your valuable comments....

thanks & regards
Sanjib

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