Re: ASM LUN sizes and number of disks

From: Finn Jorgensen <finn.oracledba_at_gmail.com>
Date: Fri, 7 Nov 2008 21:55:05 -0500
Message-ID: <74f79c6b0811071855q36b65083o86a94dd220da7d0f@mail.gmail.com>


Because of the way ASM distributes data evenly across all disks in a diskgroup, adding 200GB disks to an existing diskgroup comprising of 50GB disks means you will never be able to use more than 50GB of those 200GB disks.

You will have to add those disks to a separate diskgroup and then start moving data over, which means downtime.

Finn

On Fri, Nov 7, 2008 at 12:30 AM, hrishy <hrishys_at_yahoo.co.uk> wrote:

> Hi
>
> We have a 200Gb database and there are 6X50gb luns comprising a diskgroup
> called dataDG
>
> Since my database is growing around 100gb per year i am planning to add two
> 200Gb disks to the above diskgroups and simulatenously drop the 6 50gb disks
> off.
>
> I understand reblance would trigger in my case and i am planning to add
> 200gb disks to the luns and increase the diskgroup sizes.
>
> My question is there a formula or a rule of thumb to determine the number
> disks and the size given a database size and estimated growth rates?
>
> regards
> Hrishy
>
>
>
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>

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Received on Fri Nov 07 2008 - 20:55:05 CST

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