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From: David Miller <davem@davemloft.net>
To: therbert@google.com
Cc: netdev@vger.kernel.org
Subject: Re: [RFC PATCH] tcp: Replace possible syn attack msg by counters
Date: Wed, 10 Aug 2011 23:13:18 -0700 (PDT)	[thread overview]
Message-ID: <20110810.231318.959972077845910551.davem@davemloft.net> (raw)
In-Reply-To: <alpine.DEB.2.00.1108102229130.5341@pokey.mtv.corp.google.com>

From: Tom Herbert <therbert@google.com>
Date: Wed, 10 Aug 2011 22:38:02 -0700 (PDT)

> Rather than printing the message to the log, use a mib counter to keep
> track of the count of occurences of syn cookies being used or syn
> being dropped when request queue is full.
> 
> Rationale is these messages can fill up /var/log/messages on server
> which is simply under heavy load... I'm not sure how much more useful
> they would be in identifying a server DOS attack (compared to
> counters).
> 
> Signed-off-by: Tom Herbert <therbert@google.com>

Print the message once, and also do the counters.

Say something like "Possible SYN flooding, see SNMP counters." or
similar.

Because if people are grepping for that message in their logs, they
will now have a false sense of confidence seeing it not being there
any more.

  reply	other threads:[~2011-08-11  6:13 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-11  5:38 [RFC PATCH] tcp: Replace possible syn attack msg by counters Tom Herbert
2011-08-11  6:13 ` David Miller [this message]
2011-08-11  6:33   ` Eric Dumazet
2011-08-12  6:08     ` [PATCH] tcp: Use LIMIT_NETDEBUG in syn_flood_warning() Eric Dumazet
2011-08-15  3:20       ` Tom Herbert
2011-08-15  6:39       ` David Miller
2011-08-30 13:21 ` [PATCH v2] tcp: Change possible SYN flooding messages Eric Dumazet
2011-09-15 19:06   ` David Miller

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