Ahh...yeah, you can't back out of that new RG, it's one of the few non-reversible things in ONTAP.
 

-- Adam Fox
adamfox@netapp.com

 

From: Brent Ellis [mailto:interi@bu.edu]
Sent: Tuesday, April 03, 2007 4:11 PM
To: toasters@mathworks.com
Subject: Re: Can one change the number of disks in a raid group on the fly

More backstory, I made a mistake when I was trying  grow my aggregate and I am seeing if I can change it.  

Essentially I have two shelves attached to a fas3020c filer.  I had a aggregate(aggr0) which was set to 14 disks per raid group with 1 raid group using the disks from the 1st shelf.  and then I have 4 disks in the second shelf.  I wanted to temporarily increase the size of my aggregate so I increased the size and I expanded aggr0 onto the disks from the second shelf.  But then I realized I didn't change the raid group size.  so now I have 1 raid group with 14 disks using raid_dp and a second group with 3 disks using raid_dp and a spare.  That means for the second raid group I have only added a total of 1 disk of space while using 3 drives.  It seems like a waste so I wanted to see if I could safely backtrack or if I have to stick with it and just fill out the rest of the shelf at some point.

-Brent



On Apr 3, 2007, at 3:54 PM, Nollman, Bill wrote:

Brent;
 
Of course you can !
 
From FilerView - Go to Aggregates / Manage / Click on the aggregate to modify / Click Modify / Next
You should see "RAID Group Size" and the current number of disks per RG.
Change it from the drop down. For FC disk this can be up to 28. For SATA up to 16 (with RAID-DP).
 
Keep in mind that larger RG's will mean longer reconstruct time when you lose a disk.
 
And Adam's note about back filling is correct as well....but only need to worry about that with more than 2 RG's.
 
Bill Nollman
NetApp SE - Hartford, CT.
Cell: (860)-212-9466
 

From: Brent Ellis [mailto:interi@bu.edu]
Sent: Tuesday, April 03, 2007 2:51 PM
To: toasters@mathworks.com
Subject: Can one change the number of disks in a raid group on the fly

Question about resizing raid groups.  Can one change the number of disks in a raid group on the fly in a netapp filer?  I currently have an aggregate with a single raid groups and I would like to add another shelf.  So as to reduce the amount of storage I lose can I change the size of the raid group and grow the underlying raid for the aggregate or do I have to start a new raid group?

Brent Ellis
Computing Services Group
Boston University