From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michal Soltys <soltys@ziu.info>
Subject: Re: Alignment of RAID on specific boundary
Date: Tue, 05 Jan 2010 08:50:21 +0100
Message-ID: <4B42EF3D.9000507@ziu.info>
References: <7b3edae11001041130n42d053fcpc4923b22278c5671@mail.gmail.com> <4877c76c1001042257h49103054t977de11410eb65c6@mail.gmail.com>
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To: Michael Evans <mjevans1983@gmail.com>
Cc: Khelben Blackstaff <eye.of.the.8eholder@gmail.com>, linux-raid@vger.kernel.org
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Michael Evans wrote:
> 
> It starts the LVM2 header after 0x3000 bytes (64K chunk size); I'd
> hope to see it around 0x10000.
> 
> It looks like the data isn't padded up to the desired offset.
> 
> I agree, it would be useful to have an option to specify the offset of
> the first data chunk.


Regarding lvm, you can use --dataalignment and --metadatasize for that purpose. 
Recent lvm versions, when creating directly on md raid (and assuming recent kernel), 
should align themselves automatically:

http://www.redhat.com/archives/linux-lvm/2009-September/msg00092.html