From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jim Westfall Subject: ipv6 secondary ips and default ipv6 ip for new outbound connections Date: Fri, 18 Mar 2011 16:03:12 -0700 Message-ID: <20110318230312.GX13831@surrealistic.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: netdev@vger.kernel.org Return-path: Received: from whipper.surrealistic.net ([75.151.103.193]:52477 "EHLO whipper.surrealistic.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754690Ab1CRXMc (ORCPT ); Fri, 18 Mar 2011 19:12:32 -0400 Received: from jwestfall by whipper.surrealistic.net with local (Exim 4.69) (envelope-from ) id 1Q0ihM-0007KA-Ap for netdev@vger.kernel.org; Fri, 18 Mar 2011 16:03:12 -0700 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: Hi On ipv4 the first ip added to a nic will be used as the source ip for new outbound connections. Any additional ips, in the same netblock, will be added as secondaries. ipv6 seems to have the opposite behavior. The last ipv6 ip added to a nic is be used for new outbound connections. ~# ip -6 addr list br0 11: br0: mtu 1500 inet6 fe80::21a:64ff:fe12:54bd/64 scope link valid_lft forever preferred_lft forever ~# ip addr add 2600:c00:0:1::1101/64 dev br0 ~# traceroute6 www.kame.net | head -0 traceroute to orange.kame.net (2001:200:dff:fff1:216:3eff:feb1:44d7) from 2600:c00:0:1::1101, 30 hops max, 16 byte packets ~# ip addr add 2600:c00:0:1::1102/64 dev br0 ~# traceroute6 www.kame.net | head -0 traceroute to orange.kame.net (2001:200:dff:fff1:216:3eff:feb1:44d7) from 2600:c00:0:1::1102, 30 hops max, 16 byte packets ~# ip -6 addr list br0 11: br0: mtu 1500 inet6 2600:c00:0:1::1102/64 scope global valid_lft forever preferred_lft forever inet6 2600:c00:0:1::1101/64 scope global valid_lft forever preferred_lft forever inet6 fe80::21a:64ff:fe12:54bd/64 scope link valid_lft forever preferred_lft forever This makes things a bit of a pita when dealing with floater ipv6 ips for HA. This there some way to change this behavior to be like ipv4 or force a specific ipv6 ip to be the default used for new outbound connections? thanks Jim Westfall