2012-07-27 11:13 AM
I have an new shelf with 24 SATA disks. I want to create an 64 bit aggregate with raidsize 15. But what I want is this:
I want to balance the number of disks into two raid groups 11 (RG1) + 11(RG2) + 2 spares = 24.
How do I force it to reflect this configuration? Also does Netapp automatically calculate the number of spare disks to reserve?
Solved! SEE THE SOLUTION
2012-07-27 11:18 AM
“aggr create aggr-name -r raid-size …” where raid-size is raid group size.
Every disk not used for aggregate is spare disk. NetApp does not automatically reserves anything. It is up to you to use correct number of disks and leave enough spares.
2012-07-27 11:22 AM
But what I want is I don’t want to fill up the raidsize yet. Therefore, I want it to be raidsize of 15 but only put 11 in it so I can create two raid groups with two spares.
Now I am thinking, maybe create the aggr first as raidsize 11 and then just increase the raidsize to 15 after the aggregate is created. What do you think?
2012-07-27 11:27 AM
You can always increase raid group size later when you need to add more disks. Personally I think that having raidsize option different from actual raid group size is just confusing, but it is of course up to you how you handle it.
2012-07-27 11:33 AM
The reason being is I don’t want the raidgroup to be unbalance, where one will be 15 disks and the other just 7.
Speaking of changing the raidsize I have an existing aggregate in which I want to raidsize so I can add two more disk. Base on what you said, it means it is safe to increase the raidsize of an aggregate with existing data? No downtime or data loss?
2012-07-27 11:38 AM
I mean, I do not understand, why you would want actual raid group size 11 while having raidsize option 15. This is just confusing to anyone looking at configuration.
Yes, it is possible to increase raidsize at any time without downtime or data loss.
2012-07-27 11:49 AM
You only need to create the aggregate with 11 disks on each controller. this way, the disks, will be balanced between the controllers.
In future, when you need to add more disks you only need to put the same amount on each controller and add them to the aggregate.
2012-07-27 11:49 AM
What you can do, is first use a raid size of 11.
The disks will the be in the rigth raidsize(11-11) and balanced.
After creating, change to raidsize 15
Be aware that if you after that add disks, the first raidgroup will be populated to 15.
or you can add disk to a specific raidgroup by entering the command aggr add aggregatename -f -g rg0(or rg1) diskname