From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5CDDFC433E0 for ; Mon, 3 Aug 2020 07:47:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1384C206E2 for ; Mon, 3 Aug 2020 07:47:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=preining.info header.i=@preining.info header.b="mrC/5FiZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725946AbgHCHrt (ORCPT ); Mon, 3 Aug 2020 03:47:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725933AbgHCHrs (ORCPT ); Mon, 3 Aug 2020 03:47:48 -0400 Received: from hz.preining.info (hz.preining.info [IPv6:2a01:4f9:2a:1a08::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA144C06174A for ; Mon, 3 Aug 2020 00:47:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=preining.info; s=201909; h=In-Reply-To:Content-Type:MIME-Version:References :Message-ID:Subject:To:From:Date:Sender:Reply-To:Cc:Content-Transfer-Encoding :Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=4g5nMoWh5s0VXRfXHELzAL8yum2edVO/swpF7fIEIrQ=; b=mrC/5FiZF8Lz2nsbK4gLadHcz1 oVDzs/kCDtgVne98Vrf8r6LZtkqGGEpKQk/zxMx4HsRvtp8uj72EJbuoo89E40M2b6VHoisSWkA+A /9RxiY1KijUPhHJoswTjxgQvm+cDrd9UgME7A3C08r6IivhzO8q9ph0dnvTdcKHUka/WA/4iaMOrq C+QN67w6Ei2t4/MOHOaH6rux70cUWKXdxn4pPds46w61vgAnhZhcPJgBy64zgURHA1z+frSpj7SOc Ivc/9mfTwO8SGa3ljscYTHU53cwCZLWNc07lGRMgQeWUo/9/3W67SOF3SRHKllQwb6rXI/zfK4XfI k+zgayGQ==; Received: from tvk213002.tvk.ne.jp ([180.94.213.2] helo=burischnitzel.preining.info) by hz.preining.info with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1k2VCC-0006lg-Em for linux-btrfs@vger.kernel.org; Mon, 03 Aug 2020 07:47:44 +0000 Received: by burischnitzel.preining.info (Postfix, from userid 1000) id A00AB983AF4E; Mon, 3 Aug 2020 16:47:41 +0900 (JST) Date: Mon, 3 Aug 2020 16:47:41 +0900 From: Norbert Preining To: Btrfs BTRFS Subject: Re: replacing a disk in a btrfs multi disk array with raid10 Message-ID: <20200803074741.GB24782@burischnitzel.preining.info> References: <20200803052651.GA685777@bulldog.preining.info> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Hi Chris, thanks for your answer, that is very much appreciated. On Mon, 03 Aug 2020, Chris Murphy wrote: > Some of these are considered normal. I suggest making sure each > https://raid.wiki.kernel.org/index.php/Timeout_Mismatch Thanks, will read up on that. > Once you've done that, do a btrfs scrub. Happening regularly, but I will kick one off anyway. > btrfs replace will work whether the drive is present or not. It's just > safer to do it with the drive present because you don't have to mount > degraded. Ok. I wasn't sure about whether I can mount without -o degraded because all the metadata and data is on raid1. And then, I don't know what the Debian initramfs is doing - that is probably the more interesting surprise. > > - add the new device > > Use 'btrfs replace' Thanks, noted. > Currently 'btrfs replace' does require a separate resize step. 'device > add' doesn't, resize is implied by the command. This is somehow a logic approach, I agree. > > - start a new rebalancing > > (for the rebalance, do I need to give the > > same -dconvert=raid1 -mconvert=raid1 arguments?) > > Not necessary. But it's worth checking 'btrfs fi us -T' and making > sure everything is raid1 as you expect. Thanks, good to know. Again, thanks a lot for all the details - I couldn't deduce most of them from the wiki page on multiple devices. Your email is extremely helpful! All the best Norbert -- PREINING Norbert https://www.preining.info Accelia Inc. + IFMGA ProGuide + TU Wien + JAIST + TeX Live + Debian Dev GPG: 0x860CDC13 fp: F7D8 A928 26E3 16A1 9FA0 ACF0 6CAC A448 860C DC13