From mboxrd@z Thu Jan 1 00:00:00 1970 From: Goswin von Brederlow Subject: Re: md homehost Date: Wed, 24 Feb 2010 14:41:16 +0100 Message-ID: <87d3zulpj7.fsf@frosties.localdomain> References: <20100218044004.GC5136@lapse.rw.madduck.net> <20100218161012.704b43a6@notabene.brown> <20100218052145.GA7178@lapse.rw.madduck.net> <20100218163448.0d3f3107@notabene.brown> <20100219004237.GC25162@lapse.rw.madduck.net> <20100219091619.GA2964@lazy.lzy> <20100221174007.GB19058@lapse.rw.madduck.net> <20100221201304.GB2570@lazy.lzy> <20100222091632.GE2641@lapse.rw.madduck.net> <20100223133028.279e0174@notabene.brown> <20100223062700.GB19666@lapse.rw.madduck.net> <20100224111006.7024c84e@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: <20100224111006.7024c84e@notabene.brown> (Neil Brown's message of "Wed, 24 Feb 2010 11:10:06 +1100") Sender: linux-raid-owner@vger.kernel.org To: Neil Brown Cc: martin f krafft , Piergiorgio Sartor , 567468@bugs.debian.org, Daniel Reurich , linux-raid List-Id: linux-raid.ids Neil Brown writes: > On Tue, 23 Feb 2010 07:27:00 +0100 > martin f krafft wrote: >> The only issue homehost protects against, I think, is machines that >> use /dev/md0 directly from grub.conf or fstab. > > That is exactly correct. If no code or config file depends on a name like > /dev/mdX or /dev/md/foo, then you don't need to be concerned about the whole > homehost thing. > You can either mount by fs-uuid, or mount e.g. > /dev/disk/by-id/md-uuid-8fd0af3f:4fbb94ea:12cc2127:f9855db5 What if you have two raids (one local, one from the other hosts that broke down) and both have LVM on it with /dev/vg/root? Shouldn't it only assemble the local raid (as md0 or whatever) and then only start the local volume group? If it assembles the remote raid as /dev/md127 as well then lvm will have problems and the boot will likely (even randomly) go wrong since only one VG can be activated. I think it is pretty common for admins to configure LVM to the same volume group name on different systems. So if you consider raids being pluged into other systems please keep this in mind. MfG Goswin