On 9/20/06, Brosseau, Paul Paul.Brosseau@netapp.com wrote:
Mixing disk sizes in an aggregate is not a problem as long as you create RAID groups for each kind of disk. WAFL creates stripes at the RAID group level. For best results create complete RAID groups each time you add disks to an aggregate.
Paulb
Paul and others, Is there way to force an aggregate to start a new RAID group when an existing RAID group is not completely full. Here's a situation FAS270 with 2 shelves with 144GB FC drives. RG size is set to 16 for a single aggregate with 26 disks (2 spares). This resulted in 2 RAID groups, 1 with 16 disks and the other with 10. Now we plan to add a 3rd shelf with 300GB FC drives. If we do the regular "aggr add" it will first add the 2 spare 144GB drives, then add 4 new 300GB drives by right sizing them to match the 144GB ones. In order to maximize the capacity on this aggregate, I'd prefer to add 12 of the new drives to a new RAID group but within the same aggregate. Is something like this possible?
Haven't tried this as we don't have the new shelf yet, but can I reduce the raidsize option for the aggregate from 16 to 12, then add the 2 existing spares such that that the 2nd raid-group is now full based on raidsize=12 option. Now add the new shelf and run "aggr add aggr0 12" to add 12 new 300GB drive leaving 2 spares? RAID group /aggr0/plex0/rg0 - 16 disks (144GB each) RAID group /aggr0/plex0/rg1 - 12 disks (144GB each) <-- add the existing 2 spares RAID group /aggr0/plex0/rg2 - 12 disks (300GB each) Spares - two new 300GB drives.
I think it would work, any comments?
-G