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From: Wols Lists <antlists@youngman.org.uk>
To: NeilBrown <neilb@suse.com>,
	Gandalf Corvotempesta <gandalf.corvotempesta@gmail.com>,
	Linux RAID Mailing List <linux-raid@vger.kernel.org>
Subject: Re: 3-way mirror to RAID-6
Date: Tue, 26 Dec 2017 10:09:45 +0000	[thread overview]
Message-ID: <5A421FE9.8000200@youngman.org.uk> (raw)
In-Reply-To: <87incu79uw.fsf@notabene.neil.brown.name>

On 25/12/17 21:53, NeilBrown wrote:
> On Mon, Dec 25 2017, Gandalf Corvotempesta wrote:
> 
>> Hi to all
>> I have a server with a 3way mirror.
>> As I have to increase the total available space, one solution would be to
>> replace all disks with bigger ones, but this is expensive.
>>
>> Another solution would be to add just one disk and then reshape from
>> RAID-1 to RAID-6
>>
>> Do you have any guide on how to do this reshape on a running array ?
>> Thank you.
> 
> I suggest you add the new device with "mdadm --add", then try the
> reshape with "mdadm --grow /dev/mdXXX --level=6 --raid-devices-4".
> 
> It might not work quite that easily - I think you need to first convert
> the raid1 to a 2-way mirror, but that is easy enough
> 
>  mdadm --grow /dev/mdxxx --raid-devices=2

That was my reaction. I'm 99% certain that a three-way will not reshape.
> 
> NeilBrown
> 
Cheers,
Wol

  reply	other threads:[~2017-12-26 10:09 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-25 19:36 3-way mirror to RAID-6 Gandalf Corvotempesta
2017-12-25 21:53 ` NeilBrown
2017-12-26 10:09   ` Wols Lists [this message]
2017-12-27 10:13   ` Gandalf Corvotempesta
2017-12-27 14:28     ` Phil Turmel
     [not found]       ` <CAJH6TXiqsd=Zs4t5qAEe19shJFgSAZ1W-95yT041H6OyLbKvfA@mail.gmail.com>
2017-12-28 12:34         ` Phil Turmel
2018-01-08 11:34           ` Gandalf Corvotempesta
2018-01-08 15:20             ` Wols Lists
2018-01-08 15:25               ` Gandalf Corvotempesta
2018-01-08 20:18                 ` Wol's lists

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