From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [PATCH] net: ipv6: Make address flushing on ifdown optional Date: Tue, 16 Feb 2016 20:45:58 -0700 Message-ID: <56C3ECF6.9090103@cumulusnetworks.com> References: <1455402207-9217-1-git-send-email-dsa@cumulusnetworks.com> <56C2E1BD.30006@miraclelinux.com> <56C33D5F.2060005@cumulusnetworks.com> <56C3D6A3.7030605@miraclelinux.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit Cc: hannes@stressinduktion.org To: YOSHIFUJI Hideaki , netdev@vger.kernel.org Return-path: Received: from mail-io0-f178.google.com ([209.85.223.178]:34891 "EHLO mail-io0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965182AbcBQDqB (ORCPT ); Tue, 16 Feb 2016 22:46:01 -0500 Received: by mail-io0-f178.google.com with SMTP id g203so20088967iof.2 for ; Tue, 16 Feb 2016 19:46:00 -0800 (PST) In-Reply-To: <56C3D6A3.7030605@miraclelinux.com> Sender: netdev-owner@vger.kernel.org List-ID: On 2/16/16 7:10 PM, YOSHIFUJI Hideaki wrote: > Hi, > > David Ahern wrote: >> On 2/16/16 1:45 AM, YOSHIFUJI Hideaki wrote: >>>> diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt >>>> index 24ce97f42d35..7ddbbb67f0db 100644 >>>> --- a/Documentation/networking/ip-sysctl.txt >>>> +++ b/Documentation/networking/ip-sysctl.txt >>>> @@ -1563,6 +1563,12 @@ temp_prefered_lft - INTEGER >>>> Preferred lifetime (in seconds) for temporary addresses. >>>> Default: 86400 (1 day) >>>> >>>> +keep_addr_on_down - BOOLEAN >>>> + Keep all IPv6 addresses on an interface down event. If set static >>>> + global addresses with no expiration time are not flushed. >>>> + >>>> + Default: disabled >>>> + >>> >>> How about this: >>> 1: enabled >>> 0: system default >>> -1: disabled >>> so that an iterface can override system-wide config? >> >> It is my understanding that the 'all' settings override the individual >> interface settings. From Documentation/networking/ip-sysctl.txt +1346: >> >> conf/all/*: >> Change all the interface-specific settings. > > Well, document is not correct. > 1) Some of "all" variables set all interface specific settings. > 2) Some of "all" variables override interface specific settings. > 3) Some provide "fall-back" values; such an interface specific > setting overrides the corresponding "all" variable. > (Note: "default" variables are values per-interface settings > are initialized to.) > 4) Others are ignored (the exists but no-ops). Seems like a nightmare for an admin to understand which ones fall into which category. I really don't have a preference here beyond having the feature and making it easy to enable (e.g., enable 'all' and it works for all). If you want the 1/0/-1 trio and allow individual netdev settings to override all then I will update the patch. Thanks, David