From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?iso-8859-1?Q?Fran=E7ois-Xavier_Le_Bail?= Subject: Re: [PATCH net-next] IPv6: enable TCP to use an anycast address Date: Wed, 22 Jan 2014 06:32:36 -0800 (PST) Message-ID: <1390401156.61208.YahooMailBasic@web125501.mail.ne1.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Cc: netdev@vger.kernel.org, David Stevens , Hannes Frederic Sowa , David Miller , Hideaki Yoshifuji To: Alexey Kuznetsov Return-path: Received: from nm41.bullet.mail.ne1.yahoo.com ([98.138.120.48]:44695 "EHLO nm41.bullet.mail.ne1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755695AbaAVOfW convert rfc822-to-8bit (ORCPT ); Wed, 22 Jan 2014 09:35:22 -0500 Sender: netdev-owner@vger.kernel.org List-ID: Hello, > Actually, I was alerted by reset processing in your patch, it cannot be right. Perhaps, I missed something. My tests were: 1) enable anycast in tcp_v6_conn_request(). So, a client-serveur exchange with anycast destination address is possible. 2) try to connect with a port not listen by the server. With unicast destination address, the client got a reset. With anycast destination address, no reset, the client try several syn and give up. 3) enable anycast in tcp_v6_send_reset(). With anycast destination address, the client got a reset. So unicast and anycast behave the same. Do you see any problem with this behaviour ? > Do not you think this must not be enabled for common use? At least > some separate sysctl disabled by default. We could indeed use a sysctl, disabled by default. But my goal was to enable anycast address usage transparently, if possible. It's only a possibility for some use cases and if it's dont break unicast TCP usage, like I think it, I propose to enable this change without sysctl. So, my proposals for the TCP case, in descending order of preference are: 1) No sysctl. 2) A sysctl disabled par default, used in tcp_v6_conn_request() and tcp_v6_send_reset(). 3) A sysctl disabled par default, used in tcp_v6_send_reset(), if problem only here. Greetings, Francois-Xavier