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=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 A7B26C433B4 for ; Thu, 6 May 2021 09:57:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60B5E61157 for ; Thu, 6 May 2021 09:57:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234255AbhEFJ6b (ORCPT ); Thu, 6 May 2021 05:58:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231194AbhEFJ63 (ORCPT ); Thu, 6 May 2021 05:58:29 -0400 Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2FF7AC061574 for ; Thu, 6 May 2021 02:57:29 -0700 (PDT) Received: by mail-ej1-x629.google.com with SMTP id t4so7450216ejo.0 for ; Thu, 06 May 2021 02:57:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=s3c8ts/Y8MyxKMOUDa2u8BfyvnchBXo3B8pkZP55ZFo=; b=d4IjYv0+e0jwV11YToZ9/hrqsdSSK+BqLrvU6rqh3+H6eEuQjCosyZos/bWzGCC/Qz 21tR9KVk7ytNKiAhCF5k1nSdf5RPOgG/c0F59Qe5tc3BXhjCIBcp3glSlUK8D/3Q5T8Z IXXI4lRHJwQc0fmxzgdacl8tzrPxFq8LVbaoYtY3vAXLM6ouddvlPlsL7K7Bj9a4hcZZ I0W+G8olxD0BlwIfnF6jBWTS3TiTyXXjHJnqtZvkGkc+0ErWuoJFH8onMMyZFaYpMVCv M0mDg8xnMtNOeZRimK2ebWXQpuwBmFdbA0sss5pzeT2Ix6XfwJ5+ymzWbvZB5qgfwL3k AQfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=s3c8ts/Y8MyxKMOUDa2u8BfyvnchBXo3B8pkZP55ZFo=; b=boMlJNtGoWmsjMkRvmqdMbJXPvpkkR25Nt9UajVYTwPGxtfUdVjDHMJfZLfF37Id6G emZ0a0aY1tTb2ND88PeqJMIE7BNDkAIXA6m9daELbbHWGsXp4aYgntcaRME9LSXaVKBt AyXJNjUXWmsyaZNvb9I6JUqGCjGXzD1nu6FJlOQBtPdRxit7MlrCxT/gSjov8M2nmLuP ezFhzFxW4ay2QKsSnZlBkq3RXNXXVurDJYluWaUKWeY2IavEWTxRCZkcqR/0soTdrly2 F3jsWxOHmenjK7L7fo53MwaGPLeXDI85s1mjFoGqmpDU9vra0JLJcyMdr48lrLlYBXP9 FtsA== X-Gm-Message-State: AOAM532n/7xr/8y9OtdZ/ero2ye0R2qP9DzRnZlnsg4kLLIqXgx+ze7v HliGpjDUtm2bw3gYdggSG56O1E5CvU+6fAMrByCWktC9Z9qYYw== X-Google-Smtp-Source: ABdhPJxHGwWYoDRQmwh3tcWDhuaFz5251/iwgIMHZ5iZdEfH/d1T9mSZR6OGY5zwzerRW98TNcScQBA/+4Pm6vJzkBw= X-Received: by 2002:a17:906:c1c9:: with SMTP id bw9mr3538298ejb.239.1620295047853; Thu, 06 May 2021 02:57:27 -0700 (PDT) MIME-Version: 1.0 References: <8626adeb-696c-7778-2d5e-0718ed6aefdb@redhat.com> In-Reply-To: <8626adeb-696c-7778-2d5e-0718ed6aefdb@redhat.com> From: d tbsky Date: Thu, 6 May 2021 17:57:17 +0800 Message-ID: Subject: Re: raid10 redundancy To: Xiao Ni Cc: list Linux RAID Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org Xiao Ni > > Hi > > It depends on which layout do you use and the copies you specify. There > is a detailed description in `man md 3` Thanks a lot for the hint. After studying the pattern I think n2 and o2 could survive if losing two correct disks with 4 or 5 disks. but f2 will be dead. is my understanding correct? will n2 and o2 be promised with the same pattern even if I grow the disk numbers, like 3->4, or 4->5? if losing two disks will madam find out the raid can be rebuilded safely or not? I should try this myself, but I hope I can get some knowledge before trying... Thanks again for any help.