From mboxrd@z Thu Jan 1 00:00:00 1970 From: Harald Welte Subject: Remove IPv6 ND prefix on ethernet disconnect? Date: Wed, 22 Jun 2011 23:41:29 +0200 Message-ID: <20110622214129.GA30521@prithivi.gnumonks.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: netdev@vger.kernel.org Return-path: Received: from ganesha.gnumonks.org ([213.95.27.120]:58949 "EHLO ganesha.gnumonks.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758899Ab1FVVlf (ORCPT ); Wed, 22 Jun 2011 17:41:35 -0400 Received: from uucp by ganesha.gnumonks.org with local-bsmtp (Exim 4.72) (envelope-from ) id 1QZVB0-0002za-On for netdev@vger.kernel.org; Wed, 22 Jun 2011 23:41:34 +0200 Received: from laforge by nataraja.de.gnumonks.org with local (Exim 4.76) (envelope-from ) id 1QZVAv-0007x1-Dn for netdev@vger.kernel.org; Wed, 22 Jun 2011 23:41:29 +0200 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: Hi all, I know I've lost a bit touch with the Linux networking area in recent years... Nonetheless, there's one thing that's been bugging me for a long time and I'm thinking of investing some time to resolve it. Before doing that, I'm curious to see if there are existing solutions or existing discussions that I've missed on the subject: Imagine a setting where somebody is carrying a laptop around all day, visiting several sites (office, customer, home,...) without rebooting the machine (suspend to ram or disk). You start at home in the morning, you get an IPv6 prefix via auto-discovery, everything is fine. Now you move along to your office, but despite the link down and link up events, the IPv6 prefix remains configured. You may or may not get a new prefix, but based on my experience, in both cases you experience errors following up: 1) in the case of the new prefix, the old default route/prefix is still used 2) in case there is no new prefix, the kernel happily sends ipv6 packets to the non-existant router of a completely different network. Now I presume that those things are supposedly resolved by NetworkManager, but I don't really see why a complex and large userspace program should be required for something as simple as removing prefixes that have prevously been added automatically. My point is: If it's the kernel that automatically adds it, why is it not the kernel that automatically deletes it when it is no longer safe to assume it is valid (such as after loosing the link)? Any input is appreciated. Regards, Harald -- - Harald Welte http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)