From: NeilBrown <neilb@suse.de>
To: Neil Matai <neil@matai.kiwi.nz>
Cc: linux-raid@vger.kernel.org
Subject: Re: Simultaneous assembly on multiple hosts
Date: Mon, 6 May 2013 16:32:03 +1000 [thread overview]
Message-ID: <20130506163203.7a65786b@notabene.brown> (raw)
In-Reply-To: <20130504020146.GD31411@chc-5.metaname.net>
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On Sat, 4 May 2013 14:01:46 +1200 Neil Matai <neil@matai.kiwi.nz> wrote:
> Hi all,
>
> Is it dangerous have an array assembled on two hosts at the same time?
> Say I have servers A and B exporting devices a and b via ATA over
> Ethernet or similar to hosts C and D. If a and b are components of an
> array then both C and D automatically assemble the array as soon as
> the components a and b are exported but is this safe (on the proviso
> that only one of C or D is ever writing to the array at any time and
> that there is no write-behind caching above the array device)?
>
Yes, it is dangerous.
Both hosts will try to update the metadata and will trip over each other.
NeilBrown
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next prev parent reply other threads:[~2013-05-06 6:32 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-05-04 2:01 Simultaneous assembly on multiple hosts Neil Matai
[not found] ` <CALFpzo6CUZSeAcNK1A=8HdyjaGnKiN4Mtt01u_w=3p7WG-wY2A@mail.gmail.com>
2013-05-04 3:22 ` Neil Matai
2013-05-06 6:32 ` NeilBrown [this message]
2013-05-06 9:05 ` Sebastian Riemer
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