From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luca Berra Subject: Re: [Patch] mdadm ignoring homehost? Date: Mon, 20 Apr 2009 14:26:10 +0200 Message-ID: <20090420122610.GA17461@maude.comedia.it> References: <18899.61151.445765.360191@notabene.brown> <51C39605-BBE7-48E8-AB35-D55D0B36B3A6@redhat.com> <18919.64597.426128.498393@notabene.brown> <20090418081239.GB2124@maude.comedia.it> <18924.4416.635979.452887@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Return-path: Content-Disposition: inline In-Reply-To: <18924.4416.635979.452887@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: LinuxRaid List-Id: linux-raid.ids On Mon, Apr 20, 2009 at 04:08:00PM +1000, Neil Brown wrote: >On Saturday April 18, dledford@redhat.com wrote: >> >> I've been thinking about this, and this is the method I would suggest. >> >> Add two new keywords to the mdadm.conf file: >> >> ASSEMBLE >> INCREMENTAL >> >> Allow each of those keywords to have one of three set values: >> None - Don't attempt to assemble any arrays regardless of whether or >> not they are in the mdadm.conf file or not >> Known - Only assemble arrays with a matching array line >> All - Attempt to assemble any array found >> >> The combination of the two options and the three settings would allow >> you to control mdadm behavior for both array assembly modes >> independently. That, combined with my previous patch, should allow >> arrays to assemble well, with known names, allow you to control auto >> assembly by udev, and in the event that your machine just exports >> volumes to other machines for their use, stop assembly entirely. > >Why "None"?? Why would you use "None" rather than "Known" with an >empty list of arrays? i believe ASSEMBLE is intended as AUTO ASSEMBLE so we would have the description for the arry and be able to assemble it manually using: mdadm -A /dev/md/foo i would like to be able to define this per array tough >Why have two options: ASSEMBLE and INCREMENTAL ?? >If what circumstance would you use different settings for these two >options. maybe i want to avoid incremental assemble of a big array, which would result in undesired rebuilds. >I current have two patches sitting in my scratch queue. I am by no >means committed to them. > >One allows you to have e.g. > > ARRAY ignore UUID=foo:bar:dead:beef > >with the meaning that auto-assembly will ignore that array. If you >run > > mdadm --assemble /dev/md/thing --uuid foo:bar:dead:beef > >it will still assemble the array, but any auto-assembly will ignore >it. it is not clear to me what the difference is from having no line at all >The other allows you to say: > > AUTO -ddf -0.90 +all > >which means don't auto-assemble any 'ddf' or '0.90' array, but do >auto-assemble anything else that is recognised. >You might want to use dmraid for ddf?? > >If you just have > > AUTO -all > one syntax or the other is ok for me, provided the ability to control what mdadm is doing. L. -- Luca Berra -- bluca@comedia.it Communication Media & Services S.r.l. /"\ \ / ASCII RIBBON CAMPAIGN X AGAINST HTML MAIL / \