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 From:  Manuel Kasper <mk at neon1 dot net>
 To:  Brandon Holland <brandon at cookssaw dot com>
 Cc:  m0n0wall at lists dot m0n0 dot ch
 Subject:  Re: [m0n0wall] m0n0wall dropping packets when using bittorrent
 Date:  Mon, 26 Jan 2004 11:49:04 +0100
Brandon Holland wrote:

> Let me clarify: m0n0 even logs my dropped packets.  Now, I'm not using
> bittorrent either, but the concept is the same.
> By the way, I should have finished reading your message before I asked
> if you had tried any other firewalls :)

Logged dropped packets? Well if they are logged then there was a reason 
to drop them - a block rule (or no matching pass rule). Common reason:

- TCP packets that ipfilter considers to be out-of-window or otherwise 
unacceptable (it checks various things such as flags, 3-way handshake 
adherance, sequence/ACK numbers, etc.) and that therefore don't match an 
entry in the state table but don't have only SYN set either --> blocked 
(stateful filtering!)

Otherwise you'll have to use the rule numbers in the logs to find out 
which rule actually caused the packet to be dropped (ipfstat -hnio on 

And to those with asymmetric links: remember that any uncapped upload 
can easily "kill" your connection (render it extremely slow) - use the 
traffic shaper or limit the outbound speed in your P2P filesharing tools! ;)

- Manuel