From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Brown Subject: Re: (boot time consequences of) Linux mdadm superblock question. Date: Thu, 18 Feb 2010 16:34:48 +1100 Message-ID: <20100218163448.0d3f3107@notabene.brown> References: <20100217181016.GA14983@emergent.ellipticsemi.com> <201002171927.07051.volkerarmin@googlemail.com> <20100217183703.GA15446@emergent.ellipticsemi.com> <20100218102407.49f73d67@notabene.brown> <20100218025809.GA20358@khazad-dum.debian.net> <20100218032610.GB1991@lapse.rw.madduck.net> <1266465801.11568.183.camel@localhost.localdomain> <20100218044004.GC5136@lapse.rw.madduck.net> <20100218161012.704b43a6@notabene.brown> <20100218052145.GA7178@lapse.rw.madduck.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20100218052145.GA7178@lapse.rw.madduck.net> Sender: linux-raid-owner@vger.kernel.org To: martin f krafft Cc: Daniel Reurich , linux-raid List-Id: linux-raid.ids On Thu, 18 Feb 2010 18:21:45 +1300 martin f krafft wrote: > also sprach Neil Brown [2010.02.18.1810 +1300]: > > You would put it in /etc/mdadm.conf > > The format would be something like: > > > > ARRAY /dev/md/root uuid=xxxx:xxxx:xxxx:xxxx > > > > and any array found with that uuid would be assembled as /dev/md/root > > No, we mean using the UUID of the root filesystem (vol_id, not > mdadm's UUID) as the homehost identifier, instead of the hostname. > You can set homehost to anything you like, in mdadm.conf or on the command line.. But it would be rather awkward to store the uuid of the root filesystem in the metadata for the array that stores the root filesystem (and so is created before the root filesystem)... Are you suggesting that when mdadm finds some bits that looks like the form an array it should test-assemble it, look inside for a filesystem, extra the uuid of that filesystem and compare against some known uuid before deciding whether to assemble that array or not? I hope not. So I don't think I know what is really being proposed. ?? NeilBrown