From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Alan Dorman Subject: Can you non-destructively add a new active device to an existing RAID1? Date: 18 Oct 2002 08:45:06 -0400 Sender: linux-raid-owner@vger.kernel.org Message-ID: <87elanvru5.fsf@viola.mallet-assembly.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: To: linux-raid@vger.kernel.org List-Id: linux-raid.ids During a bit of an emergency a couple of weeks ago---my laptop quit working unexpectedly---I found myself hurriedly building a new machine from parts I had lying around, and although I only had one hard drive on hand I decided to set things up so that I could pick up a second hard drive and mirror my data. Unfortunately, I appear to have done it incorrectly, in that I did not specify that there should be two devices in the mirror with one of the devices to be "missing", but instead specified one device in the mirror. Now, of course, I've had the time to pick up a second drive, and I'm wondering if there is anything I can do to get this second drive in active mirroring mode (as opposed to adding it as a hot spare) without having to copy everything to the new drive, recreate the mirror "correctly", copy everything back and then hot-add the drive? I would just like to spare myself the downtime if at all possible. Mike.