From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stan Hoeppner Subject: Re: What's the typical RAID10 setup? Date: Mon, 31 Jan 2011 14:07:05 -0600 Message-ID: <4D471669.3040303@hardwarefreak.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: =?ISO-8859-1?Q?Mathias_Bur=E9n?= Cc: Linux-RAID List-Id: linux-raid.ids Mathias Bur=E9n put forth on 1/31/2011 3:41 AM: > How would one go about expanding a 4 HDD RAID10 into a 6 HDD RAID10? > Is it "just" a matter of creating a new RAID1 array of the 2 new HDDs= , > then adding them to the RAID0, then expanding whatever is on that > (lvm, xfs, ext4)? The best way to do this "down the road" expansion is to simply create a= nother 4 drive mdraid 10 array and concatenate it to the first with LVM. My gue= ss is that you're more concerned with usable space than IOPs, so you should p= robably start with a 4 drive RAID5. Down the road, you could add a 3 drive mdr= aid 5 and concatenate that with the first array using LVM. This will avoid all k= inds of potentially messy, possibly earth shattering mdadm conversions. Runnin= g such conversions on live arrays without a reliable backup/restore capability= is just asking for trouble. Using concatenation leaves your old and new md arr= ays totally intact. http://linux.about.com/od/commands/l/blcmdl8_lvm.htm > Are there any design tips, or caveats? For example, how many disks > would you use at most, in a RAID10 setup? As many as you want, or that your hardware can support. The largest RA= ID 10 array I've setup was 40 drives. That was an FC SAN controller though, = not mdraid. --=20 Stan -- 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