DNS versus NAT ?

[Tony Finch]

Ronald F. Guilmette via Unbound-users <unbound-users at nlnetlabs.nl> wrote:
>
> For the outbound DNS query packets, does the router re-jigger the orginal
> source port numbers so that they will (hopefully) not conflict and so that
> the DNS response packets, when they arrive, can be directed appropriately
> to one machine or the other?

Yes. The long version is RFC 4787.

> And if that is the case, then will my SOHO router catch fire if and when
> I elect to send out through it a set of 65536 or more separate DNS queries,
> all in rapid succession?

Almost certainly :-) Even quite big NAT boxes will get indigestion if you
put a lot of DNS traffic through them. In general it's best to keep
stateful middleboxes away from DNS servers. In your case you are probably
better off either setting up a DMZ at home (if they will give you multiple
IP addresses) or get a colo box for high volume DNS query traffic.

Tony.
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