Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751944AbWISMGH (ORCPT ); Tue, 19 Sep 2006 08:06:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751943AbWISMGH (ORCPT ); Tue, 19 Sep 2006 08:06:07 -0400 Received: from main.gmane.org ([80.91.229.2]:44193 "EHLO ciao.gmane.org") by vger.kernel.org with ESMTP id S1751944AbWISMGF (ORCPT ); Tue, 19 Sep 2006 08:06:05 -0400 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org From: Samuel Tardieu Subject: Re: TCP stack behaviour question Date: 19 Sep 2006 14:03:30 +0200 Message-ID: <87wt802hd9.fsf@willow.rfc1149.net> References: <005a01c6db50$587929c0$294b82ce@stuartm> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Complaints-To: usenet@sea.gmane.org X-Gmane-NNTP-Posting-Host: zaphod.rfc1149.net User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.4 X-Leafnode-NNTP-Posting-Host: 2001:6f8:37a:2::2 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1012 Lines: 18 >>>>> "Stuart" == Stuart MacDonald writes: Stuart> I suppose that the TCP retransmits aren't being sent because Stuart> the ethernet and/or IP layers don't know what's going on, Stuart> which is what's producing the arps. Is that correct? It seems correct. You cannot expect TCP packets to be sent if the target is supposedly on a directly connected network and ARP cannot get its MAC address. What should the IP layer put as the MAC address if it is unknown? You may want to run another test with another unreachable target located after a router, so that the MAC address of the router is used on the wire. You should see all the TCP retransmits you expect to see. Sam -- Samuel Tardieu -- sam@rfc1149.net -- http://www.rfc1149.net/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/