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=-5.3 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 BED3CC4363D for ; Tue, 6 Oct 2020 22:24:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 74ABD208C7 for ; Tue, 6 Oct 2020 22:24:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726672AbgJFWYG (ORCPT ); Tue, 6 Oct 2020 18:24:06 -0400 Received: from smtp.hosts.co.uk ([85.233.160.19]:46725 "EHLO smtp.hosts.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726171AbgJFWYF (ORCPT ); Tue, 6 Oct 2020 18:24:05 -0400 Received: from host86-157-96-171.range86-157.btcentralplus.com ([86.157.96.171] helo=[192.168.1.65]) by smtp.hosts.co.uk with esmtpa (Exim) (envelope-from ) id 1kPvNL-0004dm-9G; Tue, 06 Oct 2020 23:24:04 +0100 Subject: Re: pls help/review: fed 32 | LVM over raid1, on SSDs & spinning disks To: Reindl Harald , linux-raid@zq3q.org, Linux-RAID References: <202010061607.096G7CgT4052287@epjdn.zq3q.org> <1f21b8cb-a9eb-74e8-24b5-550d016b6473@thelounge.net> From: antlists Message-ID: <1ab44a42-9824-b2f6-7acc-3de446a5cba4@youngman.org.uk> Date: Tue, 6 Oct 2020 23:24:03 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.1 MIME-Version: 1.0 In-Reply-To: <1f21b8cb-a9eb-74e8-24b5-550d016b6473@thelounge.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org On 06/10/2020 18:00, Reindl Harald wrote: > Am 06.10.20 um 18:07 schrieb linux-raid@zq3q.org: >> Is it possible to get the 2MiB "bios boot" partition into raid1? >> This seems to be the most vulnerable part of my setup. > should be no problem when you have the same partitioning on all disks, > "BIOS boot" normally have no writes at boot time > > RAID1 is handeled like a single disk at early boot > > the only thing you need to do manually is install the bootloaer on all > disks and don#t forget repeat it after replace one > Very much so ... > the only thing i am not sure is the partition type, until now my setups > are MBR and sda1 is a RAID1 over all 4 disks And the raid type. Is the bios boot accessed as part of the boot sequence - sounds like it must be :-) ? Anything that might be accessed by something *before* linux is loaded, needs to be a 1.0 superblock. (I won't recommend 0.9 as it's obsolete.) That way, provided you ONLY access it to read, you can access the filesystem directly and bypass the raid by referencing the partition eg /dev/sda1. Then once linux has booted and mounted /dev/md1, any changes will be made to both partitions. Cheers, Wol