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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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