Re: Raid 5 - not clean and then a failure.

--- On Wed, 26/8/09, Goswin von Brederlow <goswin-v-b@web.de> wrote:

From: Goswin von Brederlow <redacted>
Subject: Re: Raid 5 - not clean and then a failure.
To: Jon@eHardcastle.com
Cc: linux-raid@vger.kernel.org
Date: Wednesday, 26 August, 2009, 12:18 PM
Jon Hardcastle [off-list ref]
writes:

quoted

Guys,

I have been having some problems with my arrays that I

think i have nailed down to a pci controller (well I say
that - it is always the drives connected to *a* controller
but I have tried 2!) anyway the latest saga is i was trying
some new kernel options last night - which didn't work.

quoted

But when i booted up again this morning it said one of

the drives was in an inconsistent state (not sure of the
*exact* error message). I then kicked off an add of the
drive and it started syncing. It got about 5% in and then
the second drive in on that controller complained and the
array failed. 

quoted

Is there any hope for my data? If i get a good

controller in there will the resync continue? can I try and
tell it to assume the drives are good (which they ought to
be)?

quoted

Please help!

The inconsistency is probably just a block here or there
and I'm
assuming none of your drives actualy failed. So 99.9999% of
your data
should be there. Just rebooting might actualy just get your
raid back
(to syncing). If not then you have to force reassembly from
the drives
with the newest serials. That will give you some data
corruption,
whatever was writing when the controler gave errors. Worst
case you
have to recreate the raid with --assume-clean.

I recommend adding a bitmap to the raid. That way a
wrongfully failed
drive can be resynced in a matter of minutes instead of
hours or
days. Makes it way less likely another error occurs during
resync.

MfG
        Goswin
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I did look into bitmaps *abit* i could easily have the imagine for my 6 drive raid 5 stored on the raid1 I have in the same system.. The googling I did tho did not paint a pretty picture it talked about huge performance hits?

-----------------------
N: Jon Hardcastle
E: Jon@eHardcastle.com
'Do not worry about tomorrow, for tomorrow will bring worries of its own.'
-----------------------


      
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