From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [Bugme-new] [Bug 28282] New: forwarding turns autoconfiguration off Date: Tue, 08 Feb 2011 13:44:21 -0800 (PST) Message-ID: <20110208.134421.39185637.davem@davemloft.net> References: <20110208133408.7d447e6a.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, bugzilla-daemon@bugzilla.kernel.org, bugme-daemon@bugzilla.kernel.org, hadmut@danisch.de To: akpm@linux-foundation.org Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:48435 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751831Ab1BHVnr (ORCPT ); Tue, 8 Feb 2011 16:43:47 -0500 In-Reply-To: <20110208133408.7d447e6a.akpm@linux-foundation.org> Sender: netdev-owner@vger.kernel.org List-ID: From: Andrew Morton Date: Tue, 8 Feb 2011 13:34:08 -0800 >> Linux ethernet interfaces do not use autoconfiguration and do ignore router >> advertisings if the packet forwarding is turned on in the configuration (i.e. >> /proc/sys/net/ipv6/conf/eth0/forwarding set to 1) >> >> >> This might be wrong. >> >> IPv6 network devices can have multiple IPv6 addresses and server several >> purposes at the same time. A machine can have a statically assigned local IPv6 >> address and act as a router (e.g. to a virtual machine or a VPN tunnel) and >> thus needs to turn forwarding on, while at the same time it needs to listen to >> router advertisements and autoconfigure, e.g. because a network is connected to >> the internet through a DSL router with dynamically assigned network adresses, >> either through direct IPv6 assignment or a 6to4 tunnel. >> >> So there are cases where you need to have autoconfiguration of an IP address >> and forwarding on the same interface at the same time. Therefore, it might be >> technically wrong to have this mutually exclusive. This is a case where we're probably just following what the RFC documents state we should do, which means unless you can provide clear reference to a specification that states we should behave otherwise this isn't changing.