disable cashing

[Kevin Darcy]

yossi wrote:

>phn at icke-reklam.ipsec.nu wrote in message news:<bo6j2e$2hfe$1 at sf1.isc.org>...
>  
>
>>yossi <yossi.zadah at audiocodes.com> wrote:
>>    
>>
>>>How I can configure the dns, to disable cashing?  
>>>thanks
>>>      
>>>
>>You can't. It's a built in part of the design.
>>    
>>
>
>How can an application actively query the name server in order to
>detect the possible change, regardless of the Time To Live (TTL)
>associated with the DNS record?
>
If "the name server" is the master for the zone, then it's a moot point, 
since it's already giving the most up-to-date information available.

If "the name server" is a slave server, then, short of going out of band 
and forcing the slave to refresh, your application is at the mercy of 
replication delays.

If "the name server" is a non-authoritative (caching) server,then, 
again, short of going out of band and forcing the server to purge the 
old cache entry, there's no way to make it fetch the new data.

Of course, if your application is smart enough, it can try to find the 
master server itself. But the master server might be "hidden", i.e. it 
might be behind a firewall and not even on the same network as wherever 
your app lives. So there are no guarantees here.

                                                                         
                                    - Kevin


                                                                         
                                       - Kevin