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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 A6CD5C64E7A for ; Tue, 1 Dec 2020 10:01:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4786F206C0 for ; Tue, 1 Dec 2020 10:01:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726440AbgLAKB2 (ORCPT ); Tue, 1 Dec 2020 05:01:28 -0500 Received: from smtp.hosts.co.uk ([85.233.160.19]:9397 "EHLO smtp.hosts.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725967AbgLAKB2 (ORCPT ); Tue, 1 Dec 2020 05:01:28 -0500 Received: from host86-149-69-253.range86-149.btcentralplus.com ([86.149.69.253] helo=[192.168.1.64]) by smtp.hosts.co.uk with esmtpa (Exim) (envelope-from ) id 1kk2Sk-00012X-6y; Tue, 01 Dec 2020 10:00:46 +0000 Subject: Re: partitions & filesystems (was "Re: ???root account locked??? after removing one RAID1 hard disc") To: c.buhtz@posteo.jp References: <20201130200503.GV1415@justpickone.org> <01a571de-8ae8-3d9e-6f3d-16555ad93ea3@youngman.org.uk> <1914ec9a6f74130a8e6399c08edefdc1@posteo.de> Cc: David T-G , linux-raid@vger.kernel.org From: Wols Lists Message-ID: <5FC6144D.40208@youngman.org.uk> Date: Tue, 1 Dec 2020 10:00:45 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.0 MIME-Version: 1.0 In-Reply-To: <1914ec9a6f74130a8e6399c08edefdc1@posteo.de> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org On 01/12/20 08:45, c.buhtz@posteo.jp wrote: > I think my missunderstand depends also on my bad english? > > Am 30.11.2020 21:51 schrieb antlists: >> On 30/11/2020 20:05, David T-G wrote: >>> You don't see any "filesystem" or, more correctly, partition in your >>> >>> fdisk -l >>> >>> output because you have apparently created your filesystem on the entire >>> device (hey, I didn't know one could do that!). >> >> That, actually, is the norm. It is NOT normal to partition a raid array. > > In my understanding you are contradicting yourself here. > Is there a difference between > "create filesystem on the entire device" > and > "partition a raid array" > ? Yes. Creating a raid array on an entire device means "mdadm --create --devices sda sdb" partioning a raid array means "fdisk /dev/md127" Remember linux doesn't care what a block device is, it's a block device. So you can put a raid array directly on top of physical disks, and you can put a GPT on top of a raid array. Neither are recommended. Cheers, Wol