We have stuck with the 500GB drives for that reason so far – however, over the next few years I’m sure there will be no choice.  By then, the rules will likely have changed (as per Blake’s email).

While the default is 12D+2P on ATA, we’ve been consistently using 14D+2P to make it match our FC config and allow us to have a relatively standard approach to calculating available storage when we go to purchase stuff.  Good luck so far, but a bit hesitant to push that luck on 1TB drives.

Just make sure you stick to Raid-DP – we don’t have anything in our environment that isn’t J

Glenn

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From: owner-toasters@mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of No More Linux!
Sent: Thursday, June 05, 2008 5:47 PM
To: tmac
Cc: toasters@mathworks.com
Subject: Re: 1TB SATA, raid group size, 16TB limits etc

the point was that we needed 10TB of space on a new filer and a single 1TB drive shelf provides this but pretty much violates the redundancy and performance benefits of spreading load across multiple drives/shelves/controllers in an aggregate.

so to even make it somewhat more appropriate we would have to buy 2 shelves so the aggregate load would be more adequately spread but we still run up across the 16TB aggregate limit.

i guess the issue is with 1TB drives the whole 16TB aggregate limit is just plain silly and ridiculous.

maybe we should just go with the 500GB sata shelves and spread the load across more drives.   im not sure i want to confine my aggregates to just 8 to 12 drives max.

On Thu, Jun 5, 2008 at 12:55 PM, tmac <tmacmd@gmail.com> wrote:

Let ontap figure where to put things.

Besides,. the recommended size is 14 for SATA and 16 for FC per raid group.
Obviously, if you want to MAX out an aggregate at 16TB, you have to
take into consideration
you cannot do it in a single RAID group (well, I think you can, but it
is not recommended!!).
Therefore, your raid groups may look like 8+8 (maybe even 9+9), but
you probably do not
want 14+2 or 14+4.

Either way, you are eating the parity drives. Might as well make them
balanced groups.

Oh, one more thing. Let ONTAP pick which disks to use. It will
intelligently pick across shelves and controllers.

--tmac

On Thu, Jun 5, 2008 at 3:09 PM, No More Linux! <no.more.linux@gmail.com> wrote:
>
> is the raid group recommended size still 16 with the new 1TB sata drives?
> basically we are pretty much limited to one shelf per aggregate--not sure
> how this is good thing.
>
> is the 16tb limit going away anytime soon?  it is becoming increasingly too
> restrictive as these larger drive sizes are introduced.   or am i just
> supposed to create one shelf aggregates of 1tb drives from now on?
>
>

--
--tmac

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