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From: Alex Flex <aflexzor@gmail.com>
To: netfilter@vger.kernel.org
Subject: syncookies load testing
Date: Mon, 13 May 2013 19:15:38 -0600	[thread overview]
Message-ID: <5191903A.20708@gmail.com> (raw)

Hello Netfilter,

As some of you may know iam doing some work with syn cookies in my LAN.. 
Id like to understand the process better which is why i have a few 
questions:

Assume the system has conntrack off.

a.) I noticed that while creating a synflood with syn cookies enabled 
VRS syn cookies disabled the output of netstat remains exactly the same 
(even on different hardware architecture) ... :

[root@cl-t055-211cl ~]# netstat -nat | awk '{print $6}' | sort | uniq -c 
| sort -n
[...]
     256 SYN_RECV

Could anybody explain to me why this is so?

b.) From my understanding the syn back log is the memory of half open 
connections, could anybody tell me what effect this has on syn cookies? 
and if there is anyway to monitor its usage?

Thanks
Alex


             reply	other threads:[~2013-05-14  1:15 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-14  1:15 Alex Flex [this message]
2013-05-14  1:24 ` syncookies load testing Alex Flex

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