From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pablo Neira Ayuso <pablo@netfilter.org>
Subject: Re: nfnl_listen: recvmsg overrun: No buffer space available"
 in	nfct_event_conntrack() call
Date: Thu, 01 Feb 2007 09:58:15 +0100
Message-ID: <45C1ABA7.80600@netfilter.org>
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To: =?UTF-8?B?0J/QsNCy0LXQuyDQmtC+0LrQvtC70LXQvNC40L0=?= <pavelkok@gmail.com>
Cc: netfilter@lists.netfilter.org

Hi,

Павел Коколемин wrote:
> I am using libnetfilter_conntrack for log all connections passing via my 
> router (new & destroy messages).
> 
> When LAN users start network scanners (NetLook, for example),
> sometimes I receive error in console:
> "nfnl_listen: recvmsg overrun: No buffer space available"
> generated in nfct_event_conntrack() (recvmsg() returns ENOBUFS error code).
> This message generated in nfnl_listen().

Increase netlink buffer size via nfnl_rcvsiz() (libnfnetlink), the 
default size is available in /proc/sys/net/core/rmem_max. BTW, this 
message means that you have probably lost some log messages because the 
rate was so high that the buffer could not back off.

-- 
The dawn of the fourth age of Linux firewalling is coming; a time of 
great struggle and heroic deeds -- J.Kadlecsik got inspired by J.Morris