sw RAID a spolehlivost

[Petr Simek]

On Mon, 4 Aug 2008, Dalibor Straka wrote:

>>> Upozornit raid, ze tento disk jiz v poli byl lze parametrem --re-add.
>>
>> A ten udela kompletni resync sektor po sektoru. Vyzkousejte si to.
>>
> Neudela, skutecne to mam odzkousene.
>
> man mdadm
>
> 	If an array is using a write-intent bitmap, then devices which have
> 	been removed can be re-added in a way that avoids a full
> 	reconstruction but instead just updates the blocks that have changed
> 	since the device was removed.  For arrays with persistent metadata
> 	(superblocks) this is done automatically.  For arrays created with
> 	--build mdadm needs to be told that this device we removed recently
> 	with --re-add.

Jo a taky se tam pise

   Devices  can  only  be  removed  from  an  array if they are not in
   active use, i.e. that must be spares or failed devices.  To remove an
   active device, it must first be marked as faulty.

takze kdyz se za chodu vytahne harddisk tak to nejspis nebude ono. Ja mam
odzkousene ze kdyz tomu seberu disk tak to dela komletni resync. Mozna
to funguje bez te plne rekonstrukce jen kdyz ten disk korektne vyhodite
z pole. Na druhou stranu to ale neni moc uzitecne - vyhodit z pole a zase
ho tam vclenit. Realnejsi je to vytazeni - to simuluje poruchu verneji.

> -- Dalibor Straka

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|                          Petr Simek   APS JU                           |
|                             psimek na jcu.cz                              |
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