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Re: PROXY DNS ???



Eddie Harari writes:
 > >    the problem is that DNS use UDP datagrams , so when I try to resolve names
 > >    I connect to one of the root servers and it's reply never get thrue my cisco
 > >    so I know I can solve it by opening the udp connection ( and I have to open 
 > >    all ports because there is no way to know on what port will the reply come on
 > 
 > Nope.
 > 
 >  1. There's a source port & a destination port.  One of them will be
 >     the DNS port.
 >  2. You can only allow packets coming from the DNS server, and to your
 >     dns server, and only going to your DNS server on the appropriate
 >     port.
 > 
 > This is not so true , I cant know on what port will the udp arive , 
 > the request is on a certain port but the reply is on a different one 
 > and it is not a dynamic one ... ( I cant know it before the transmit ...). 

If the destination port of the DNS UDP packet is unknown, how does
named listen for it?


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