From owner-svn-src-head@freebsd.org Wed Jun 13 07:30:01 2018 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 25A8A100DE11; Wed, 13 Jun 2018 07:30:01 +0000 (UTC) (envelope-from freebsd@pdx.rh.CN85.dnsmgr.net) Received: from pdx.rh.CN85.dnsmgr.net (br1.CN84in.dnsmgr.net [69.59.192.140]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 78D84714AA; Wed, 13 Jun 2018 07:30:00 +0000 (UTC) (envelope-from freebsd@pdx.rh.CN85.dnsmgr.net) Received: from pdx.rh.CN85.dnsmgr.net (localhost [127.0.0.1]) by pdx.rh.CN85.dnsmgr.net (8.13.3/8.13.3) with ESMTP id w5D7Tu0m038158; Wed, 13 Jun 2018 00:29:56 -0700 (PDT) (envelope-from freebsd@pdx.rh.CN85.dnsmgr.net) Received: (from freebsd@localhost) by pdx.rh.CN85.dnsmgr.net (8.13.3/8.13.3/Submit) id w5D7TuFx038157; Wed, 13 Jun 2018 00:29:56 -0700 (PDT) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <201806130729.w5D7TuFx038157@pdx.rh.CN85.dnsmgr.net> Subject: Re: svn commit: r334875 - head/sys/net In-Reply-To: To: "Andrey V. Elsukov" Date: Wed, 13 Jun 2018 00:29:56 -0700 (PDT) CC: rgrimes@freebsd.org, src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Reply-To: rgrimes@freebsd.org X-Mailer: ELM [version 2.4ME+ PL121h (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Jun 2018 07:30:01 -0000 > On 09.06.2018 15:26, Rodney W. Grimes wrote: > >> Author: ae > >> Date: Sat Jun 9 09:57:14 2018 > >> New Revision: 334875 > >> URL: https://svnweb.freebsd.org/changeset/base/334875 > >> > >> Log: > >> Explicitly change the link state when we assingn an address. > >> > >> Since we are setting IFF_UP flag on SIOCSIFADDR, it is possible, that > >> after this link state information still not initialized properly. > >> This leads to problems with routing, since now interface has > >> IFCAP_LINKSTATE capability and a route is considered as working only > >> when interface's link state is in LINK_STATE_UP (see RT_LINK_IS_UP() > >> macro). > > > > I was going to say something when the ability to up and down > > the loopback interfaces was added as it perturbed me but I > > could not put my finger on places it may cause problems so > > remained silent on the matter. > > > > Now that I see this issue, having lo0 go DOWN can kill a network > > that is using exported from lo0 into a routing protocol routes that > > are used for management purposes. > > This was one of the main reasons of this change. > > > How does Cisco, Juniper, etc at handle this? > > Do any of them or all of them allow you to "down" loopback? > > AFAIK, they allow this. Confirmed as far as you can "shutdown/no shutdown" a loopback device on Cisco, but I am not sure that is the same as the LINK_STATE_UP/DOWN. I am fine with it as it is now, but we need to keep an eye on it for any issues. -- Rod Grimes rgrimes@freebsd.org