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From: Wols Lists <antlists@youngman.org.uk>
To: scar <scar@drigon.com>, linux-raid@vger.kernel.org
Subject: Re: moving spares into group and checking spares
Date: Wed, 14 Sep 2016 19:35:30 +0100	[thread overview]
Message-ID: <57D99872.3000802@youngman.org.uk> (raw)
In-Reply-To: <nrc2pm$2a9$1@blaine.gmane.org>

On 14/09/16 18:52, scar wrote:
> i'm not sure what you're suggesting, that 4x 11+1 RAID5 arrays should be
> changed to 1x 46+2 RAID6 array?  that doesn't seem as safe to me.  and
> checkarray isn't going to check the spare disks just as it's not doing
> now.... also that would require me to backup/restore the data so i can
> create a new array

No. The suggestion is to convert your 4x 11+1 raid5's to 4x 12 raid6's.
(or do you mean 11 drives plus 1 parity? If that's the case I mean 11
plus 2 parity)

That way you're using all the drives, they all get tested, and if a
drive fails, you're left with a degraded raid6 aka raid5 aka redundant
array. With your current setup, if a drive fails you're left with a
degraded raid5 aka raid0 aka a "disaster in waiting".

And then you can add just the one spare disk to a spares group, so if
any drive does fail, it will get rebuilt straight away.

The only problem I can see (and I should warn you) is that there seems
to be a little "upgrading in place" problem at the moment. My gut
feeling is it's down to some interaction with systemd, so if you're not
running systemd I hope it won't bite ...

Cheers,
Wol

  parent reply	other threads:[~2016-09-14 18:35 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-14  5:18 moving spares into group and checking spares scar
2016-09-14  9:29 ` Andreas Klauer
     [not found]   ` <20160914092959.GA3584-oubN3LzF/wf25t9ic+4fgA@public.gmane.org>
2016-09-14 17:52     ` scar
2016-09-14 18:22       ` Roman Mamedov
2016-09-14 21:05         ` scar
2016-09-14 22:33           ` Chris Murphy
     [not found]             ` <CAJCQCtQJwOTYsWubd0rV-6PRL4kmVRKLfLr3=7ZPr1Zb3SrwtQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-09-14 22:59               ` scar
2016-09-14 23:15                 ` Chris Murphy
     [not found]                   ` <CAJCQCtQ1GHdQtShbW3U1o-fmXhT3fHrC7S9BxsxrrOG=0H_p3A-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-09-15  3:42                     ` scar
2016-09-15  3:51                       ` Chris Murphy
     [not found]                         ` <CAJCQCtRW9REafzmyk+W6aVxqxMUWCdXNkrST1e7udrH-zp26Uw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-09-28  0:19                           ` scar
2016-09-29  1:17                             ` NeilBrown
2016-09-14 18:35       ` Wols Lists [this message]
2016-09-29  1:21 ` NeilBrown

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