From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phil Turmel Subject: Re: Soft RAID and EFI systems Date: Tue, 04 Feb 2014 07:27:51 -0500 Message-ID: <52F0DCC7.7050307@turmel.org> References: <70EFD3D5-F7AC-4359-8888-99EB6CCA9E4F@colorremedies.com> <52EEB9F2.2000607@gmail.com> <3D3B8F1A-F525-459D-95F2-9D7889C222CD@colorremedies.com> <52EECD53.30802@turmel.org> <52F0A79F.7090707@gmail.com> <52F0A976.9080306@hesbynett.no> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <52F0A976.9080306@hesbynett.no> Sender: linux-raid-owner@vger.kernel.org To: David Brown , Francis Moreau , Chris Murphy Cc: linux-raid List-Id: linux-raid.ids On 02/04/2014 03:48 AM, David Brown wrote: > On 04/02/14 09:41, Francis Moreau wrote: >> Are both v0.9 and v1.0 MD put their metadata at the end of a partition >> ? I thought only v0.9 would do that. > > Yes, it is only 0.9 format that is at the end of the partition. This > means that a plain raid1 mirror (with as many disks as you like, as long > as they are simple mirrors and not raid10) looks just like a normal > partition for other tools. As long as it is read-only, tools that are > not raid-aware can use it. For example, grub and lilo can happily boot > from a 0.9 metadata raid1 array just like from a normal partition. > (Actually, modern grub understands a lot of md raid formats.) The same > thing should apply to EFI, as long as it does not attempt to write to > the partition. No, both 0.9 and 1.0 have metadata after the data area. v1.1 and 1.2 have their metadata before the data area. I've been using v1.0 on my /boot mirrors for a long time. Phil