From: Franchoze Eric <franchoze@yandex.ru>
To: Florian Westphal <fw@strlen.de>
Cc: netdev@vger.kernel.org
Subject: Re: Re: why do we need printk on sending syn flood cookie?
Date: Mon, 02 Aug 2010 20:11:36 +0400 [thread overview]
Message-ID: <23001280765498@web50.yandex.ru> (raw)
In-Reply-To: <20100802081716.GA8374@Chamillionaire.breakpoint.cc>
02.08.10, 12:17, "Florian Westphal" <fw@strlen.de>:
> Franchoze Eric wrote:
> > Just sirious why do we need printk each 1 second (60*HZ) about possible syn-flood? It really floods dmesg. Is there something dengerous? I have suggestion to turn off printk about sending tcp cookie each 1 second.
>
> It is handled exactly like other printks in the networking path,
> e.g. receipt of tcp wscale == 15.
>
> Why does this need special treatment?
>
For now I see "possible SYN flooding on port %d. Sending cookies.\n" message each second on my server. I know that there are a lot of SYNs and I know that kernel sends cookie. Why do I need so mach printk?
So I suggested add new value to /proc/sys/net/ipv4/tcp_syncookies, which will enable cookie but this printk will be turned off.
next prev parent reply other threads:[~2010-08-02 16:11 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-02 7:58 why do we need printk on sending syn flood cookie? Franchoze Eric
2010-08-02 8:17 ` Florian Westphal
2010-08-02 16:11 ` Franchoze Eric [this message]
2010-08-02 18:10 ` Mitchell Erblich
2010-08-02 21:14 ` Franchoze Eric
2010-08-02 22:30 ` Mitchell Erblich
2010-08-02 22:48 ` Franchoze Eric
2010-08-02 22:49 ` Mitchell Erblich
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