From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Schumacher Subject: Re: ip_conntrack table is full with razor requests. Something isn't timing out. Date: Wed, 02 Mar 2005 09:58:58 -0900 Message-ID: <42260CF2.4080404@aptalaska.net> References: <4224A715.8030907@aptalaska.net> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: netfilter-bounces@lists.netfilter.org Errors-To: netfilter-bounces@lists.netfilter.org Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Jozsef Kadlecsik Cc: netfilter@lists.netfilter.org Jozsef Kadlecsik wrote: > Hi, > > On Tue, 1 Mar 2005, Matthew Schumacher wrote: > > >>Since upgrading to 2.6.10 I have been having problems with my >>ip_conntrack table filling up. It appears it is full of razor >>(http://razor.sf.net) requests from my internal mail server. >> >>I raised the ip_conntrack_max to 8192 and there are only a few hosts >>behind nat so I am certain something isn't getting flushed out. >> >>How do I go about diagnosing this. What specifically does ip_conntrack >>need to see in the tcp session to mark the session as expired in the table? > > > Run tcpdump and record at least one full session of the razor traffic. > Best is if you capture the traffic on both side of the firewall in order > to make sure nothing got lost. Collect anything relevant from the > kernel log file and attach the /proc/net/ip_conntrack lines referring to > the session. Post the collected data and then we can start to hunt down > the reason of the problem. > Jozsef, Here is the relevant part of the dump: 10:15:34.144668 IP 66.151.150.24.2703 > 64.4.232.33.54120: P 37:47(10) ack 78 win 5840 10:15:34.147076 IP 64.4.232.33.54120 > 66.151.150.24.2703: . ack 47 win 49640 10:15:34.151703 IP 64.4.232.33.54120 > 66.151.150.24.2703: P 78:83(5) ack 47 win 49640 10:15:34.153156 IP 64.4.232.33.54120 > 66.151.150.24.2703: F 83:83(0) ack 47 win 49640 10:15:34.217685 IP 66.151.150.24.2703 > 64.4.232.33.54120: . ack 83 win 5840 10:15:34.256491 IP 66.151.150.24.2703 > 64.4.232.33.54120: . ack 84 win 5840 10:15:34.311607 IP 66.151.150.24.2703 > 64.4.232.33.54120: R 47:47(0) ack 84 win 5840 Since there is a ACK before the RST it is safe to assume that the bug documented at https://lists.netfilter.org/pipermail/netfilter-devel/2004-December/017908.html was the problem. Since kernel 2.6.11 came out this morning, and the bug fix appears in the changelog, I went ahead and upgraded and the problems are resolved. If you would like more information then let me know, but at this point, I think it's safe to say that this bug is squashed. schu