From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roopa Prabhu Subject: Re: [PATCH net-next v3 0/4] net: ipv6: Improve user experience with multipath routes Date: Sun, 29 Jan 2017 18:20:24 -0800 Message-ID: <588EA2E8.2040302@cumulusnetworks.com> References: <1485559258-4856-1-git-send-email-dsa@cumulusnetworks.com> <588D3EB9.1070107@cumulusnetworks.com> <592be6dc-df0e-6185-ba6f-5acf5d042ae5@cumulusnetworks.com> <588E80DB.3070209@cumulusnetworks.com> <71e661bd-e26d-2629-06bb-888f6a09b06d@cumulusnetworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, nicolas.dichtel@6wind.com To: David Ahern Return-path: Received: from mail-pg0-f41.google.com ([74.125.83.41]:34878 "EHLO mail-pg0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750900AbdA3CUu (ORCPT ); Sun, 29 Jan 2017 21:20:50 -0500 Received: by mail-pg0-f41.google.com with SMTP id 194so96851688pgd.2 for ; Sun, 29 Jan 2017 18:20:26 -0800 (PST) In-Reply-To: <71e661bd-e26d-2629-06bb-888f6a09b06d@cumulusnetworks.com> Sender: netdev-owner@vger.kernel.org List-ID: On 1/29/17, 5:29 PM, David Ahern wrote: [snip] > Let's give an example for each case: > > 1. Add - full multipath route > > This route command: > ip -6 ro add vrf red 2001:db8:200::/120 nexthop via 2001:db8:1::2 nexthop via 2001:db8:2::2 > > generates this notification (ip -t mon ro): > > 2001:db8:200::/120 table red metric 1024 > nexthop via 2001:db8:1::2 dev eth1 weight 1 > nexthop via 2001:db8:2::2 dev eth2 weight 1 > ack, > 2. Delete - 1 notification for each hop for all combinations of delete commands here I was trying to say, for people deleting the full multipath route, you should send a RTA_MULTIPATH. For the odd case of ipv6 single nexthop delete, you can continue to send a single nexthop delete (like today ..without RTA_MULTIPATH) because there is no other way to notify a single nexthop delete with a RTM_DELROUTE. The reason I say this is because: keeping future in mind, this will make things consistent for majority of people who will start using RTA_MULTIPATH for both ipv4 and ipv6 for adds and deletes (requests/notifications and dumps) the same way. single next hop delete will just be around because of fear of breaking existing applications. > > > 3. Replace - full multipath route > > This route command (with the one from Add case already in place): > ip -6 ro replace vrf red 2001:db8:200::/120 nexthop via 2001:db8:1::16 nexthop via 2001:db8:2::16 > > generates a single notification: > > Replaced 2001:db8:200::/120 table red metric 1024 > nexthop via 2001:db8:1::16 dev eth1 weight 1 > nexthop via 2001:db8:2::16 dev eth2 weight 1 ack, > > 4. Append - 1 route after all hops are appended > > This append command (starting with the one installed from the Replace case): > ip -6 ro append vrf red 2001:db8:200::/120 nexthop via 2001:db8:2::20 nexthop via 2001:db8:1::20 > > generates a single notification: > > Append 2001:db8:200::/120 table red metric 1024 > nexthop via 2001:db8:2::20 dev eth2 weight 1 > nexthop via 2001:db8:1::20 dev eth1 weight 1 > nexthop via 2001:db8:1::16 dev eth1 weight 1 > nexthop via 2001:db8:2::16 dev eth2 weight 1 > > (The Replaced and Append annotations are due to a local iproute2 patch; iproute2 does > not currently distinguish NEWROUTE cases.) > ack, thanks