From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from email.routify.me ([162.208.10.182]:58594 "EHLO cartman.routify.me" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751648AbcAVDpl (ORCPT ); Thu, 21 Jan 2016 22:45:41 -0500 Received: from coach.student.rit.edu (coach.student.rit.edu [129.21.178.64]) by cartman.routify.me (Postfix) with ESMTPSA id 4122381A62 for ; Thu, 21 Jan 2016 22:45:40 -0500 (EST) Date: Thu, 21 Jan 2016 22:45:38 -0500 From: Sean Greenslade To: linux-btrfs@vger.kernel.org Subject: RAID1 disk upgrade method Message-ID: <20160122034538.GA25196@coach.student.rit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi, all. I have a box running a btrfs raid1 of two disks. One of the disks started reallocating sectors, so I've decided to replace it pre-emptively. And since larger disks are a bit cheaper now, I'm trading up. The current disks are 2x 2TB, and I'm going to be putting in 2x 3TB disks. Hopefully this should be reasonably straightforward, since the raid is still healthy, but I wanted to ask what the best way to go about doing this would be. I have the ability (through shuffling other drive bays around) to mount the 2 existing drives + one new drive all at once. So my first blush thought would be to mount one of the new drives, partition it, then "btrfs replace" the worse existing drive. Another possibility is to "btrfs add" the new drive, balance, then "btrfs device delete" the old drive. Would that make more sense if the old drive is still (mostly) good? Or maybe I could just create a new btrfs partiton on the new device, copy over the data, then shuffle the disks around and balance the new single partition into raid1. Which of these makes the most sense? Or is there something else I haven't thought of? System info: [sean@rat ~]$ uname -a Linux rat 4.3.3-3-ARCH #1 SMP PREEMPT Wed Jan 20 08:12:23 CET 2016 x86_64 GNU/Linux [sean@rat ~]$ btrfs --version btrfs-progs v4.3.1 All drives are spinning rust. Original raid1 was created ~Aug 2013, on kernel 3.10.6. Thanks, --Sean