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From: Mart Frauenlob <mart.frauenlob@chello.at>
To: netfilter@vger.kernel.org
Subject: Re: Disabling conntrack for local net
Date: Fri, 23 Oct 2009 08:22:22 +0200	[thread overview]
Message-ID: <4AE14B9E.9050705@chello.at> (raw)
In-Reply-To: <4AE13AA6.5080509@chello.at>

Mart Frauenlob wrote:
> Gary Smith wrote:
>> We have several IP's NAT'd in from public interface.  Even with that 
>> we noticed that 80% or so of the connection entries appear to be 
>> local to local traffic.
>>
>> We have the following subnets
>>
>> 10.40.16.0/24 (NAT'd public)
>> 10.40.17.0/24 (internal data)
>> 10.40.18.0/24 (internal data)
>> 10.40.19.0/24 (internal data)
>> 10.40.20.0/24 (NAT'd public)
>>
>> Public internface NAT's mostly to 10.40.16.0/24 IP's, and a couple on 
>> the 10.40.20.0/24 IP's.  We have data/internal services on the 
>> 10.40.17.0/24 and 10.40.18.0/24.  We see lots of connections from the 
>> 10.40.16.0/24 to the data/internal getting entered into the conntrack 
>> (as you would normally expect). 
>> So, is there any benefit of not conntracking these?  Is so, how do I 
>> do that without breaking the NAT.
>>
>> I know I did this years ago, I just can't remember how.
>>   
>
> Benefit = No resources used on connection tracking
>
> -t raw -m -s x.x.x.x/zz -d y.y.y.y/zz -j NOTRACK
>
sorry, missed that:
or the RAWNAT target from the xtables addon if you used NAT.

  reply	other threads:[~2009-10-23  6:22 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-23  3:00 Disabling conntrack for local net Gary Smith
2009-10-23  5:09 ` Mart Frauenlob
2009-10-23  6:22   ` Mart Frauenlob [this message]
2009-10-23 16:26     ` Gary Smith
2009-11-16 23:32       ` Gary Smith
2009-11-17 10:03         ` Mart Frauenlob
2009-11-17 16:35           ` Gary Smith

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