From mboxrd@z Thu Jan 1 00:00:00 1970 From: Goswin von Brederlow Subject: Re: Migrating RAID 1 volumes to Dual ported disks. Date: Tue, 03 Nov 2009 20:32:15 +0100 Message-ID: <87r5sf4d6o.fsf@frosties.localdomain> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: (Simon Jackson's message of "Tue, 3 Nov 2009 16:01:54 +0000") Sender: linux-raid-owner@vger.kernel.org To: Simon Jackson Cc: "linux-raid@vger.kernel.org" List-Id: linux-raid.ids Simon Jackson writes: > Hi. > > I am currently using SATA drives in a RAID 1 configuration. I am looking to use SAS drives instead of SATA. As my first experiment I have plugged my SAS drive into a system and I have noticed that Linux sees the individual ports on the device as separate devices, so I have /dev/sdc and /dev/sdd which are both the same physical device. > > So if I have a system with 2 SAS drives I am going to have 4 devices representing the two physical drives. So my question is how do I create RAID 1 sets for partitions on these types of drive? > > My existing system carves 3 RAID 1 volumes from a pair of drives. How do I translate this to the dual port SAS devices? > > Thanks Simon. You would set up multipath to combine the two paths to the same disk as a single device and then run raid over that. MfG Goswin