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From: Alex Flex <aflexzor@gmail.com>
To: netfilter@vger.kernel.org
Subject: Re: synflood +syncookies + conntrack strange behaviour
Date: Sat, 11 May 2013 12:05:40 -0600	[thread overview]
Message-ID: <518E8874.4090801@gmail.com> (raw)
In-Reply-To: <20130511022114.GA7793@localhost>

Pablo,

Thank you for clearing that aspect! I now understand why not always do i 
get an error...

However the following two points still have me confused..

a.) If I enable syn cookies, shouldnt it stop completely the SYN RECV 
state connections in my netstat? Because i still do get them a lot. In 
fact my tests reveal that with or without syn cookies the maximum 
connections in SYN RECV always reach 256 and then no more connections 
are allowed.

b.) I  tried disabling iptables all together (thus no conntrack) and I
still saw 100% packetloss , iam sure iamnot hitting a  cpu or link limit
because previously i hit a 100k pps 50mbits, and now iam doing half that
for testing and still using syncookies. Why would i still be lossing
packets?

Thanks
Alex


  reply	other threads:[~2013-05-11 18:05 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-10  1:04 synflood +syncookies + conntrack strange behaviour Alex Flex
2013-05-11  0:07 ` Alex Flex
2013-05-11  2:21   ` Pablo Neira Ayuso
2013-05-11 18:05     ` Alex Flex [this message]
2013-05-11 18:26 ` Pascal Hambourg
2013-05-11 18:47   ` Alex Flex

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