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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 12:47:05 -0600	[thread overview]
Message-ID: <518E9229.20504@gmail.com> (raw)
In-Reply-To: <518E8D5B.3060200@plouf.fr.eu.org>

Pascal,

Thank you for your reply.

Ok, I made sure:

a.) conntrack is 100% disabled.
b.) iptables is enabled with a simple stateless ruleset.
c.) Syn cookies is enabled.

The issue is: In my testing Iam still being able to exaust *something* 
because immediately when i hit  a syn flood on port 80 (medium size) I 
get imediate packet loss (as seen through ICMP, also i cannot ssh in the 
machine and unable to reach port 80.

IF i disable syncookies then: I can ping the machine fine no packetloss 
but I cannot reach port 80 (seems this port is the only one in packetloss)

Question: What resource can be exausted both when syncookies is enabled 
and disabled for this to happen?

Thanks

Alex

      reply	other threads:[~2013-05-11 18:47 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
2013-05-11 18:26 ` Pascal Hambourg
2013-05-11 18:47   ` Alex Flex [this message]

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