From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.jrs-s.net ([173.230.137.22]:33029 "EHLO mail.jrs-s.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754002AbaACXk0 (ORCPT ); Fri, 3 Jan 2014 18:40:26 -0500 Message-ID: <52C74B00.7080906@jrs-s.net> Date: Fri, 03 Jan 2014 18:42:56 -0500 From: Jim Salter MIME-Version: 1.0 To: Freddie Cash CC: =?UTF-8?B?Sm9zaHVhIFNjaMO8bGVy?= , linux-btrfs , Chris Murphy Subject: Re: btrfs raid1 and btrfs raid10 arrays NOT REDUNDANT References: <52C73987.7000106@jrs-s.net> <52C73D1A.8060805@gmail.com> <52C7402A.7050605@jrs-s.net> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: For anybody else interested, if you want your system to automatically boot a degraded btrfs array, here are my crib notes, verified working: ***************************** boot degraded 1. edit /etc/grub.d/10_linux, add degraded to the rootflags GRUB_CMDLINE_LINUX="rootflags=degraded,subvol=${rootsubvol} ${GRUB_CMDLINE_LINUX} 2. add degraded to options in /etc/fstab also UUID=bf9ea9b9-54a7-4efc-8003-6ac0b344c6b5 / btrfs defaults,degraded,subvol=@ 0 1 3. Update and reinstall GRUB to all boot disks update-grub grub-install /dev/vda grub-install /dev/vdb Now you have a system which will automatically start a degraded array. ****************************************************** Side note: sorry, but I absolutely don't buy the argument that "the system won't boot without you driving down to its physical location, standing in front of it, and hammering panickily at a BusyBox prompt" is the best way to find out your array is degraded. I'll set up a Nagios module to check for degraded arrays using btrfs fi list instead, thanks... On 01/03/2014 06:06 PM, Freddie Cash wrote: > Why is manual intervention even needed? Why isn't the filesystem > "smart" enough to mount in a degraded mode automatically?​ > > -- > Freddie Cash > fjwcash@gmail.com