From mboxrd@z Thu Jan  1 00:00:00 1970
From: "saeed bishara" <saeed.bishara@gmail.com>
Subject: Re: Linux RAID migration
Date: Tue, 7 Aug 2007 14:31:00 +0300
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To: Neil Brown <neilb@suse.de>
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On 8/7/07, Neil Brown <neilb@suse.de> wrote:
> On Tuesday August 7, saeed.bishara@gmail.com wrote:
> > how can I create raid 5 array that preserves the contents of a given
> > disk (part of the array)?
> > I can do that in two steps, raid 5 on two disks then reshape it to be
> > real raid5, but is there a direct way to do it?
>
> What do you mean by "real raid 5".  Two disks are just as much an
> array as 10.
I meant by real raid 5 to raid 5 over 3 drives or above.
> What do you mean by "direct".  If I understand your requirements
in one mdadm command
> correctly, there are two obvious steps.
>   1/ make the data appear in a raid5
>   2/ change the number of devices in the raid5.
>
> Are two steps too many?
in this case I two options:
1. keep the filesystem unmounted tell step 1 in done -> the fs will
not be available for long time
2. force umount before step 2.


>
> I guess I don't understand your question.
>
> NeilBrown
>