My comments below.
On Nov 21, tomi.rautio@nokia.com wrote:
Hello there,
is it possible to add mode disks in certain raidgroup.
I already have raidgroup 0 and 1, all disks in same/one vol0.
Raid group0: 14 disks and group1:28 disks and I want to add more disks in group0, How?
Sorry you can't. To the best of my knowledge, you can only add disks to the raid group most recently created. And by the way, 28 disks in one raid group??? IMHO, that's a lot. What kind of reconstruct times are you seeing for that? I have always used 7 max. It gives pretty good reconstruct times.
This is true. The only way to change the number of disks in the first raid group(rg0) is to destroy the volume and recreate the volume being sure to change the raidsize option as follows:
vol options vol0 raidsize 28
If you want 28 disks in your first raid group. I agree with Aaron's comment about reconstruct speed. Also the larger the number of disks in a single raid group the higher the odds of data loss due to duble disk failure. Please be aware that if you have too few disks in a raid group you could also negatively affect the performance. Check this white paper on www.netapp.com
http://www.netapp.com/tech_library/3008.html
According to the "Table 4" in this technical paper 14 disks per raid group provides optimal performance.