From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phil Turmel Subject: Re: [BUG] non-metadata arrays cannot use more than 27 component devices Date: Wed, 1 Mar 2017 13:13:13 -0500 Message-ID: <2d168cc1-cddc-5e0c-610b-97cbd08de621@turmel.org> References: <20170224040816.41f2f372.ian_bruce@mail.ru> <41ea334c-ae1c-dac6-e1a1-480d3700a588@turmel.org> <20170224084024.4dfe83a2.ian_bruce@mail.ru> <1e40da0d-b175-9ff5-d2e5-cf1f25aacc26@turmel.org> <58B2137B.6070608@youngman.org.uk> <5172e2ab-e193-477b-52c4-86fbab0d52fe@turmel.org> <58B21987.6060604@youngman.org.uk> <657e80e9-b1f5-1f58-a4d0-6cbc4cc44927@turmel.org> <58B6E287.9020804@youngman.org.uk> <27373f29-a8ea-012c-102d-9fadf05cb3c2@turmel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <27373f29-a8ea-012c-102d-9fadf05cb3c2@turmel.org> Sender: linux-raid-owner@vger.kernel.org To: Wols Lists , ian_bruce@mail.ru, linux-raid@vger.kernel.org List-Id: linux-raid.ids On 03/01/2017 12:23 PM, Phil Turmel wrote: > I strongly disagree. This procedure, as shown, is an admin cock-up: > >> mdadm --build /dev/mdbackup --device-count 2 /dev/md/home missing >> ... hotplug sd-big ... >> madam /dev/mdbackup --add /dev/sd-big >> ... wait for sync to finish ... >> mdadm --stop mdbackup >> ... unplug sd-big ... One more point. The above is functionally identical in every respect to just: # dd if=/dev/md/home of=/dev/sd-big bs=1M Why are you bothering to --build an array? Phil