From mboxrd@z Thu Jan 1 00:00:00 1970 From: roopa Subject: Re: [PATCH net-next 7/8] mpls: Multicast route table change notifications Date: Wed, 25 Feb 2015 23:21:11 -0800 Message-ID: <54EEC967.20106@cumulusnetworks.com> References: <87pp8xx6ik.fsf@x220.int.ebiederm.org> <87fv9tvrgq.fsf@x220.int.ebiederm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: David Miller , netdev@vger.kernel.org, Stephen Hemminger , santiago@crfreenet.org, Vivek Venkatraman To: "Eric W. Biederman" Return-path: Received: from mail-pd0-f178.google.com ([209.85.192.178]:36765 "EHLO mail-pd0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750862AbbBZHVO (ORCPT ); Thu, 26 Feb 2015 02:21:14 -0500 Received: by pdjp10 with SMTP id p10so11054813pdj.3 for ; Wed, 25 Feb 2015 23:21:13 -0800 (PST) In-Reply-To: <87fv9tvrgq.fsf@x220.int.ebiederm.org> Sender: netdev-owner@vger.kernel.org List-ID: On 2/25/15, 9:19 AM, Eric W. Biederman wrote: > Unlike IPv4 this code notifies on all cases where mpls routes > are added or removed as that was the simplest to implement. > > In particular routes being removed because a network interface > goes down or is removed are notified about. Are there technical > arguments for handling this differently ? Userspace developers > don't particularly like the way IPv4 handles route removal > on ifdown. that is true. However, from previous emails on this topic on netdev, there is no reason to notify these deletes to userspace thereby creating a notification storm when userspace can figure this out. Which seems like a valid reason. (Your approach resembles IPv6 which does generate these notifications and userspace is usually happy with this). Thanks.