ONTAP Discussions

Separate root aggregate?

goepel
5,576 Views

We have a customer that set up a standard practice of creating separate 32 bit root aggregates for filers in 7.x.  Now with 8.0.1 there is no longer a requirement to provision storage in new filers with a separate 32 bit root aggregate.  My question:

Is it still considered a best practice to have a separate 32 bit root aggregate (3 spindles wasted) or is the new best practice to build a single large  64 bit aggr0 with the root volume contained in that aggregate?

I understand that with the root volume and data contained in the same aggregate an online WAFLIRON of that aggregate cannot take place.  Is this the only limitation?  Is it enough to continue driving customers toward a separate root aggregate?

6 REPLIES 6

ajeffrey
5,576 Views

I would point your customer here:  http://now.netapp.com/NOW/knowledge/docs/ontap/rel801/pdfs/ontap/smg.pdf  page 159

All of the pros and cons are laid out there.

goepel
5,576 Views

Thanks!  That is somewhat helpful to the customer but doesn't give them any information they don't already know.  I wonder if there are any field people reading this that can share what their own customers are doing.

andrc
5,576 Views

TBH I haven't encountered anyone who creates a separate aggregate for the root volume.I guess it comes down to each individual customer and how much of a risk they feel it is to have the root volume and data volumes in one aggregate, compared to how much of a waste they feel it is to sacrifice two/three disks for a small root volume.

chriskranz
5,576 Views

If the system is big enough, then I'd always create a dedicated root aggregate. Does this make any difference if it's 32bit or 64bit? Currently I see no real advantage either way, you're not gaining any benefit from going 64bit. That being said, it may future proof the system to go 64bit on the root aggregate, and as there's now no technical limitations on doing this, I'd probably go down that route.

If there system is a 2000 series of any variety, you simply don't have the storage to dedicate a root aggregate, but the rest of the range the benefits are worth considering. It's similar to aggregate snapshots, you may never use them, but when you do, you'll be so thankful you have them!!!

columbus_admin
5,576 Views

Having worked for a large US financial institution and supported 700+ filers, we did not have a separate aggregate for root anywhere.  Simple reason is using a 300GB drive, I have to dedicate three disks, or 900GB, now imagine a 2TB SATA build!  6TB for a volume that on the largest system is 300G. You can't get away with RAID4 on your root volume, because disk firmware updates are disruptive on RAID4 builds.

The one hit most people bring up is wafliron, which we have never had to run....In my current position we still do not dedicate a separate root vol because of the wasted space invovled.  As drives continue to get bigger, it translates to more and more wasted space.

- Scott

Anita
4,402 Views

Hello, 

 

I am not able to access the link you have provided.

 

http://now.netapp.com/NOW/knowledge/docs/ontap/rel801/pdfs/ontap/smg.pdf

 

Regards,

Anita

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