From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Evans Subject: Re: Device role question Date: Fri, 26 Feb 2010 21:56:02 -0800 Message-ID: <4877c76c1002262156k6675877am79a7da9b63446dc7@mail.gmail.com> References: <20100226142331.GA2328@lazy.lzy> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20100226142331.GA2328@lazy.lzy> Sender: linux-raid-owner@vger.kernel.org To: Piergiorgio Sartor Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Fri, Feb 26, 2010 at 6:23 AM, Piergiorgio Sartor wrote: > Hi all, > > checking randomly the component of some RAID-10 arrays > (two disks each), with "mdadm -E /dev/sdXY", I noticed > the following. > > There is an entry reported, called "Device Role". > > On one array, the components are defined, respectively, as: > > Active device 0 > Active device 1 > > On another two arrays, it's a bit different. > > Active device 0 > spare > > Why is it "spare" (all are RAID-10 f2)? > > Does it make any difference one or the other role, in > this type of RAID? > > On the other hand, "mdadm -D /dev/mdX" does not seem > to give any hint on the different roles. > > Thanks, > > bye, > > -- > > piergiorgio > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > Spare should mean that it is not currently a synced member of the array; in other words a hot-spare. As I recall raid10 cannot currently be grown (or /may/ only be grown with VERY recent tools+kernels); did you maybe create a single device raid10 and try to grow it? -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html