Agreed.

-----Original Message----- From: Fox, Adam [mailto:Adam.Fox@netapp.com] Sent: Wednesday, January 10, 2007 5:31 PM To: Glenn Walker; Willeke, Jochen; tmac Cc: toasters@mathworks.com Subject: RE: add bigger disk into raidgroup with smaller disks

Yes, I can confirm that. But that doesn't *replace* any of the 50GB disks, which is what I understood as the original question. The rules are different if you add a disk vs. fail out a disk. If you were to fail out one of the 50GB disks in your scenario, and only a 100GB disk was available, WAFL would only use 50GB of the 100GB disk and even if you failed out both 50GB disks, the two 100GB disks that replaced them would still be 50GB.

That's the catch.

-- Adam Fox NGS Tools Developer adamfox@netapp.com

-----Original Message----- From: Glenn Walker [mailto:ggwalker@mindspring.com] Sent: Wednesday, January 10, 2007 5:07 PM To: Willeke, Jochen; tmac; Fox, Adam Cc: toasters@mathworks.com Subject: RE: add bigger disk into raidgroup with smaller disks

I can't seem to shake the memory of one other rule - if you add a 3rd disk of larger size, the extra space DOES get used. At least it used to be like that in the past, and I assume WAFL hasn't changed.

For Example

100GB DP 100GB P 50GB D 50GB D

Then add another 100GB data disk and it _should_ look like:

100GB DP 100GB P 100GB D 50GB D 50GB D

Can anyone confirm this?

Glenn

-----Original Message----- From: owner-toasters@mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Willeke, Jochen Sent: Wednesday, January 10, 2007 4:19 PM To: tmac; Fox, Adam Cc: toasters@mathworks.com Subject: RE: add bigger disk into raidgroup with smaller disks

Hi,

thanks...what you said is exactly what my tests showed. If the parity and DP are big enough you can run disks with different size in a raidgroup and use the whole size but this does not work if a small disk becomes replaced via a bigger one.

thanks and best regards

Jochen

-----Original Message----- From: tmac [mailto:tmacmd@gmail.com] Sent: Wednesday, January 10, 2007 10:14 PM To: Fox, Adam Cc: Willeke, Jochen; toasters@mathworks.com Subject: Re: add bigger disk into raidgroup with smaller disks

Sorry Adam, I used the wrong verbiage.

I meant when the disk is added...not replaced.

For now, ONTAP does indeed right-size a disk down to the size of the disk that it is replacing.

thanks.

On 1/10/07, Fox, Adam Adam.Fox@netapp.com wrote:

No. You can't replace disks in an aggregate that way. If you do, they will sized down to the size of the disk they replaced.

-- Adam Fox adamfox@netapp.com

-----Original Message----- From: Willeke, Jochen [mailto:Jochen.Willeke@wincor-nixdorf.com] Sent: Wednesday, January 10, 2007 3:12 PM To: toasters@mathworks.com Subject: add bigger disk into raidgroup with smaller disks

Hi toasters,

currently i am testing with my simulator and searching for a way to do

the following:

• have a raidgroup with 5 disks
• the two parity-disks plus one data-disk are 100 MB (net)
• two other data-disks are 35 MB (net)

I want to replace the 35MB-disks with bigger ones, but everything i tried left the "new" disk in the raidgroup with a used size of 35MB.

Is there a way to replace a small disk with a bigger one and use the complete size of the disk without destroying the whole raidgroup?

Regards and thanks in advance

Jochen

-- --tmac

RedHat Certified Engineer #804006984323821