Re: pf.conf newbie help

From: Danilo Kempf (usenet_at_nullpointer.de)
Date: 08/25/04 

Date: Wed, 25 Aug 2004 15:00:30 +0200

> Ah, I was allowing port 53 as tcp, not udp. That is my error...

Dennis,

While passing traffic for UDP/53 will make your DNS lookups work, don't
delete your TCP/53 rule just yet.

Most of the time DNS is done via UDP, but it has a builtin limit. DNS
messages may/should not grow beyond 512 bytes. When they get longer, the
DNS server will truncate the result. Upon receiving a truncated result to a
DNS query, any sane resolver will retry the same query via TCP.

So to spare you some spurious errors, also pass TCP/53.

Regards, Danilo

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