From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f52.google.com ([209.85.215.52]:46902 "EHLO mail-lf0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751344AbeA0Gn4 (ORCPT ); Sat, 27 Jan 2018 01:43:56 -0500 Received: by mail-lf0-f52.google.com with SMTP id q194so3261440lfe.13 for ; Fri, 26 Jan 2018 22:43:56 -0800 (PST) Subject: Re: degraded permanent mount option To: Christophe Yayon , "Austin S. Hemmelgarn" , "Majordomo vger.kernel.org" References: <1516975360.4083556.1249069832.1B287A04@webmail.messagingengine.com> <5d342036-0de0-9bf7-3e9e-4885b62d8100@gmail.com> <1516978054.4103196.1249114200.76EC1546@webmail.messagingengine.com> <84c23047-522d-2529-5b16-d07ed8c28fc6@gmail.com> <1517035210.1252874.1249880112.19FABD13@webmail.messagingengine.com> From: Andrei Borzenkov Message-ID: <8607255b-98e7-5623-6f62-75d6f7cf23db@gmail.com> Date: Sat, 27 Jan 2018 09:43:53 +0300 MIME-Version: 1.0 In-Reply-To: <1517035210.1252874.1249880112.19FABD13@webmail.messagingengine.com> Content-Type: text/plain; charset=utf-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: 27.01.2018 09:40, Christophe Yayon пишет: > Hi, > > I am using archlinux with kernel 4.14, there is btrfs module in initrd. > In fstab root is mounted via UUID. As far as I know the UUID is the same > for all devices in raid array. > The system boot with no problem with degraded and only 1/2 root device. Then your initramfs does not use systemd. > -- > Christophe Yayon > cyayon-list@nbux.org > > > > On Sat, Jan 27, 2018, at 06:50, Andrei Borzenkov wrote: >> 26.01.2018 17:47, Christophe Yayon пишет: >>> Hi Austin, >>> >>> Thanks for your answer. It was my opinion too as the "degraded" >>> seems to be flagged as "Mostly OK" on btrfs wiki status page. I am >>> running Archlinux with recent kernel on all my servers (because of >>> use of btrfs as my main filesystem, i need a recent kernel).> > >>> Your idea to add a separate entry in grub.cfg with >>> rootflags=degraded is attractive, i will do this...> > >>> Just a last question, i thank that it was necessary to add >>> "degraded" option in grub.cfg AND fstab to allow boot in degraded >>> mode. I am not sure that only grub.cfg is sufficient...> > Yesterday, i have done some test and boot a a system with only 1 of >>> 2 drive in my root raid1 array. No problem with systemd,> >> Are you using systemd in your initramfs (whatever >> implementation you are> using)? I just tested with dracut using systemd dracut module and it >> does not work - it hangs forever waiting for device. Of course, >> there is> no way to abort it and go into command line ... >> >> Oh, wait - what device names are you using? I'm using mount by >> UUID and> this is where the problem starts - /dev/disk/by-uuid/xxx will >> not appear> unless all devices have been seen once ... >> >> ... and it still does not work even if I change it to root=/dev/sda1 >> explicitly because sda1 will *not* be announced as "present" to >> systemd> until all devices have been seen once ... >> >> So no, it does not work with systemd *in initramfs*. Absolutely. > >