From owner-freebsd-net Wed Feb 23 1:28:50 2000 Delivered-To: freebsd-net@freebsd.org Received: from d12lmsgate.de.ibm.com (d12lmsgate.de.ibm.com [195.212.91.199]) by hub.freebsd.org (Postfix) with ESMTP id 3CDAE37B83E; Wed, 23 Feb 2000 01:28:40 -0800 (PST) (envelope-from DRHAGER@de.ibm.com) Received: from d12relay02.de.ibm.com (d12relay02.de.ibm.com [9.165.215.23]) by d12lmsgate.de.ibm.com (1.0.0) with ESMTP id JAA64902; Wed, 23 Feb 2000 09:59:53 +0100 From: DRHAGER@de.ibm.com Received: from d12mta01.de.ibm.com (d12mta01_cs0 [9.165.222.237]) by d12relay02.de.ibm.com (8.8.8m2/NCO v2.06) with SMTP id JAA28450; Wed, 23 Feb 2000 09:59:52 +0100 Received: by d12mta01.de.ibm.com(Lotus SMTP MTA v4.6.5 (863.2 5-20-1999)) id C125688E.00316BAA ; Wed, 23 Feb 2000 09:59:48 +0100 X-Lotus-FromDomain: IBMDE To: Joao Pedras Cc: freebsd-net@FreeBSD.ORG, Freebsd-net@FreeBSD.ORG Message-ID: Date: Wed, 23 Feb 2000 09:59:27 +0100 Subject: Re: dropping connection Mime-Version: 1.0 Content-type: text/plain; charset=us-ascii Content-Disposition: inline Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org I had a similar problem: The ISDN link kept coming up every 10 min, and in tcpdump I found ICMP ECHO-REQUEST in this intervall. (*from* my net....) So the link came up and down constantly. This turned out to be PMTU Discovery re-checking a route via the link. You can find the IP of the offending machine and the process ID in the packet - I am not familiar with the tcpdump-output, sorry. Orm ######################################################################## Hello all. I have been using FreeBSD to use ordinary pc's as routers. Several of those machines use the i4b daemon. Althought this IS NOT a FreeBSD or i4b problem, I would like to submit it to your consideration, so I could have an independent opinion about it. Several of these routers connect through one of the major isp in our country. Only in these installations I face the problem of disconnection when idle after 'x' time, to don't work (i.e. no matter how I configure the isdnd it never drops the connection). The exact same configuration on other isp works properly and performs the disconnect. The problem is that this particular isp has their routers configured to send some kind of keep alive, whenever the connection is idle. I ran tcpdump on the isp0 interface and got the following : 19:45:36.787026 ID-063 LCP: Echo-Request, Magic-Number=-495599889 093f 000c e275 beef 0258 d272 19:45:36.787052 ID-063 LCP: Echo-Reply, Magic-Number=1285595741 0a3f 000c 4ca0 a25d 0258 d272 19:45:46.789844 ID-064 LCP: Echo-Request, Magic-Number=-495599889 0940 000c e275 beef 0258 d272 19:45:46.789865 ID-064 LCP: Echo-Reply, Magic-Number=1285595741 0a40 000c 4ca0 a25d 0258 d272 19:45:56.793551 ID-065 LCP: Echo-Request, Magic-Number=-495599889 0941 000c e275 beef 0258 d272 19:45:56.793570 ID-065 LCP: Echo-Reply, Magic-Number=1285595741 0a41 000c 4ca0 a25d 0258 d272 19:46:06.796127 ID-066 LCP: Echo-Request, Magic-Number=-495599889 0942 000c e275 beef 0258 d272 19:46:06.796147 ID-066 LCP: Echo-Reply, Magic-Number=1285595741 0a42 000c 4ca0 a25d 0258 d272 Frankly, I do not know of to interpret this data. Do you find this situation normal ? I spoke with them and they didn't gave me any 'real' reason to be doing this. They said they won't change their configuration. They suggested me to write some kind of filter to ignore this. Is this easily achiavable ? Just for curiosity, I read in the IOS 12.0 Configurartion book, that the keep alive in Cisco routers could be enabled optionally. I really don't see any use to this configuration. ]:( Thanks for your help Joao ^\ /^ O O ----------------------------------------o00-(_)-00o-------------------------- I often quote myself; it adds spice to my conversation. -- G. B. Shaw ----------------------------------------------------------------------------- PGP key available upon request or may be cut at http://pedras.webvolution.net/pgpkey.html To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message