From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ralf Spenneberg <lists@spenneberg.org>
Subject: Re: Protecting against DoS
Date: 09 Dec 2003 19:16:38 +0100
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To: "John A. Sullivan III" <john.sullivan@nexusmgmt.com>
Cc: Geffrey =?ISO-8859-1?Q?Vel=E1squez?= <g_netfilter@netfids.com>, Netfilter <netfilter@lists.netfilter.org>

Hi,

Am Die, 2003-12-09 um 19.01 schrieb John A. Sullivan III:
> > > echo 1 > /proc/sys/net/ipv4/tcp_syncookies -- if you have not compile=
d
> >=20
> >=20
> > Is that valid for forwarded packets? or only destinated to the firewall=
?
This is valid only for local packets.

> We have avoided using these /proc settings for just that concern - that
> they are mostly for the gateway itself and not for the devices being
> protected by it whether it is anti-spoofing with rp_filter or protecting
> against syn_floods.  Is this assumption of ours true? Thanks, all - John
Actually it depends. Most just concern local packets, but
rp_filter and accept_source_route for example tests for all packets.


Cheers,

Ralf
--=20
Ralf Spenneberg
RHCE, RHCX

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