2013-09-17 04:39 AM
should I have a big aggregate each controller containing all all 4x[23-24] drives and multiple RG, or multiple aggregates?
it is on 2x3240 HA, 64-bit aggr, ontap 8.2.x,and for NAS shares. 3 drives from 3 shelv respectively have been allocated for aggr0 already.
600GB each raw
Thanks for your advice.
Solved! SEE THE SOLUTION
2013-09-17 11:17 AM
I would have one big aggregate on each controller, which means I would expand aggr0 to become 4 raidgroups of rg size 23, raid-dp. Reasons:
1. Hate wasting 3 drives for just vol0, especially if the drives, which you didn't mention, are large-capacity (e.g. 900GB SAS).
2. We use rg size 23 because we tend to add storage by shelves, and it's a lot simpler to grow the aggregates by entire shelves. Plus the disk drives keep getting bigger and bigger, so it's just really easier to deal with entire shelves at a time.
3. We like larger aggregates, and less number of aggregates. Lots of spindles for performance. We like to have one SAS aggregate and one SATA aggregate. You don't have to deal with aggregates running out of space and you have to migrate a volume to another aggregate, etc etc.
4. Less wasted disks drives.
We had NetApp consultants here for three months and this was one of their recommendations. It took me a lot of work merging aggregates (one filer pair went from about 20 aggregates or so, down to 4) and we're really happy we did this.
2013-09-18 02:38 AM
Thank you for your valuble inputs.
One more question. There will be about 8TB space and used for a backup/dumping data over, should we seprate this space and create 2nd aggregate for it? the consideration is that backup data has less performance requirement, and should not compete the I/O with other data onto the same aggregate. What is your opinion?
2013-09-18 03:19 AM
I think most Netapp users would favour reqqme914's advice over Henry's.
My added advice would be, beyond the first 20 or so, only allocate the number of disks you need to an aggregate (ensuring they're at most 80% used/ allocated), Nothing's more annoying than having to a half empty aggregate on one head and being tight for space on the other.
2013-09-18 03:55 AM
I just wanted to make sure I understand you correctly. So, you share our concern that backup data could compete I/O with primary data, therefore, are you saying that we should create 2nd aggregate (put 20 disks as you suggested), and this aggregate would be used for 8TB backup data, and it should not exceed 80% of usage?
2013-09-18 07:28 AM
Ideally, you would've had a separate SATA aggregate for your dumps, backups, etc., but you don't, so... what I would do, if I were in your position, would be to stick to the one large aggregate anyway and have more spindles for all your workloads and have the I/Os spread across all disks, and all the other benefits I've previously enumerated.
2013-09-18 08:53 AM
Hi Resqme914, Thanks again for your messages.
The problem is that there is aggr0 already created, and contained 3/raid-dp disks.
How should I do from here? Should I blow away this aggr0, and set up a new BIG aggr0, that would require redo everything already on current aggr0, including reinstall OnTap. Isn't? Or should I just leave aggr0 as it is, and create a BIG aggr1 with rest of other disks? Any suggestion on that?