From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 87293C3A59E for ; Wed, 21 Aug 2019 20:20:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2A4072070B for ; Wed, 21 Aug 2019 20:20:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=candelatech.com header.i=@candelatech.com header.b="Sv5VmAb+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729078AbfHUUUE (ORCPT ); Wed, 21 Aug 2019 16:20:04 -0400 Received: from mail2.candelatech.com ([208.74.158.173]:59004 "EHLO mail3.candelatech.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727685AbfHUUUE (ORCPT ); Wed, 21 Aug 2019 16:20:04 -0400 Received: from [172.31.98.117] (unknown [4.30.140.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail3.candelatech.com (Postfix) with ESMTPSA id 81F7B65937; Wed, 21 Aug 2019 13:20:03 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 mail3.candelatech.com 81F7B65937 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=candelatech.com; s=default; t=1566418803; bh=Eu97Kys10jTPoksJ0inbkOY3y1jtDXfYMq9UoxO1vjM=; h=Date:From:To:Subject:References:In-Reply-To:From; b=Sv5VmAb+fytmGqP3vwO06Upc9BJZPoPkCalxYSdRxGxQB38OBlmVri1X8dmRLx4Hw 5STHJp3+DgDTyofOgQCVau6WzEccLO1LqQjFlQoY/YSpDQugPaHDr4cVg6NZl3AEYT wUxfNj/g9CePjxvUw7qi5AR9sxiuiv0wZNYF2Z4w= Message-ID: <5D5DA773.6000100@candelatech.com> Date: Wed, 21 Aug 2019 13:20:03 -0700 From: Ben Greear Organization: Candela Technologies User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: David Ahern , netdev Subject: Re: VRF notes when using ipv6 and flushing tables. References: <8977a25e-29c1-5375-cc97-950dc7c2eb0f@candelatech.com> <2a8914bb-56ec-e585-bd76-36b77ca2517d@gmail.com> In-Reply-To: <2a8914bb-56ec-e585-bd76-36b77ca2517d@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 08/20/2019 08:02 PM, David Ahern wrote: > On 8/20/19 2:27 PM, Ben Greear wrote: >> I recently spend a few days debugging what in the end was user error on >> my part. >> >> Here are my notes in hope they help someone else. >> >> First, 'ip -6 route show vrf vrfX' will not show some of the >> routes (like local routes) that will show up with >> 'ip -6 route show table X', where X == vrfX's table-id >> >> If you run 'ip -6 route flush table X', then you will loose all of the auto >> generated routes, including anycast, ff00::/8, and local routes. >> >> ff00::/8 is needed for neigh discovery to work (probably among other >> things) >> >> local route is needed or packets won't actually be accepted up the stack >> (I think that is the symptom at least) >> >> Not sure exactly what anycast does, but I'm guessing it is required for >> something useful. >> >> You must manually re-add those to the table unless you for certain know >> that >> you do not need them for whatever reason. >> > > sorry you went through such a long and painful debugging session. No problem. I learned some details of IPv6 I never realized before, sure to come in useful some day! Thanks, Ben > yes, the kernel doc for VRF needs to be updated that 'ip route show vrf > X' and 'ip route show table X' are different ('show vrf' mimics the main > table in not showing local, broadcast, anycast; 'table vrf' shows all). > > A suggestion for others: the documentation and selftests directory have > a lot of VRF examples now. If something basic is not working (e.g., arp > or neigh discovery), see if it works there and if so compare the outputs > of the route table along the way. -- Ben Greear Candela Technologies Inc http://www.candelatech.com