From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Brown Subject: Re: [Patch] mdadm ignoring homehost? Date: Mon, 20 Apr 2009 16:08:00 +1000 Message-ID: <18924.4416.635979.452887@notabene.brown> 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> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: message from Doug Ledford on Saturday April 18 Sender: linux-raid-owner@vger.kernel.org To: Doug Ledford Cc: Luca Berra , LinuxRaid List-Id: linux-raid.ids 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? Why have two options: ASSEMBLE and INCREMENTAL ?? If what circumstance would you use different settings for these two options. 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. 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 then it won't auto-assemble anything, which is much like your ASSEMBLE Known INCREMENTAL Known NeilBrown