From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 5085 invoked by alias); 13 Nov 2018 16:49:16 -0000 Mailing-List: contact libc-help-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Post: List-Help: , Sender: libc-help-owner@sourceware.org Received: (qmail 4088 invoked by uid 89); 13 Nov 2018 16:49:14 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-1.3 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,KAM_NUMSUBJECT,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=no version=3.3.2 spammy=phillip, 6724, getaddrinfo, contracting X-HELO: mail-ot1-f42.google.com Received: from mail-ot1-f42.google.com (HELO mail-ot1-f42.google.com) (209.85.210.42) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 13 Nov 2018 16:49:13 +0000 Received: by mail-ot1-f42.google.com with SMTP id g27so11932085oth.6 for ; Tue, 13 Nov 2018 08:49:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=GHDir17iZcfI4ny8VmU72IqY1otIP2Rvb40WIv4HfH0=; b=Jzr+AyshM6l4kjG0dIEYU+uHhUOcKQF2czvn5F9jwGK7yLbnz8+fTecRAwhYnE9nGl zwWxeXjlQF8czDANTn8361tLjPXCCrtf1diO7y8o6V/dbXZyY0xK/9oBx9y23X6SWoVj qQHHQJw7ijITb8AMtURzwKF7pp+48ihBc+92xegToR9ZNEhwil9AtCQS8g8B5nwx/0fv XlItgaTOiZdReVpV+o6xOJOxeY6JtLMtARPZ8474dRYKHrsNZVY65899ytTS30Gco23u qec7GGXkPH2KtcXFavIqLQdKIJj2Pu4RoiMxo6Qdl/7SZ/NiIZ2w3XqEGjHfmnkpWR/0 WDDw== MIME-Version: 1.0 References: <87lg5yr17v.fsf@oldenburg.str.redhat.com> <87ftw6nqcv.fsf@oldenburg.str.redhat.com> <87d0r9l06y.fsf@oldenburg.str.redhat.com> In-Reply-To: <87d0r9l06y.fsf@oldenburg.str.redhat.com> From: Phillip Hellewell Date: Tue, 13 Nov 2018 16:49:00 -0000 Message-ID: Subject: Re: RFC 6724 To: fweimer@redhat.com Cc: libc-help@sourceware.org Content-Type: text/plain; charset="UTF-8" X-IsSubscribed: yes X-SW-Source: 2018-11/txt/msg00012.txt.bz2 On Tue, Nov 13, 2018 at 3:51 AM Florian Weimer wrote: > > I'm more interested in arguments for preferring some IPv4 addresses over > IPv6 address in the destination selection algorithm, and IPv6 over IPv4 > in other cases. In general I believe there are two goals: 1. Prefer global scope over local scope. 2. Prefer IPv6 over IPv4 (except for old/obsolete/unreliable IPv6 mechanisms). I believe #1 takes precedence over #2, hence the reason why an IPv4 could be preferred over IPv6 in some cases. > I'm not sure if the kernel has a concept of a home address. That seems > to be something that would be maintained by higher-level tools such as > NetworkManager or systemd. That's fine. Then ignore rule 4 as far as getaddrinfo is concerned. That doesn't mean throw the whole RFC out the window. RFC 3484 had that rule too. All I'm asking is that the default policy table be updated; since RFC 6724 came out 6 years ago it surprises me that it hasn't already been updated. But at the same time I'm contracting myself because actually I don't want the table to be updated unless we also address the concern that local IPv6 should be preferred over local IPv4. Phillip