I'd have to agree. Most of my customers with 250/270s are looking for
space, not performance. Flexvols mean they only have to give up 2 disks
to parity (most also make root a flexvol)
Michael Cope
NetApp Professional Services Engineer
mcope(a)NetApp.com
Cell: (858) 204-2400
txt msg: 8582042400(a)vtext.com
Simplifying Data Storage Management
-----Original Message-----
From: Fox, Adam
Sent: Monday, June 05, 2006 5:21 PM
To: Blake Golliher; Michael Homa
Cc: toasters(a)mathworks.com
Subject: RE: Suggestions regarding migration from 740 to 270
It really depends on your situation. FlexVols on small systems can be
really useful, especially if you need multiple volumes or have small
data sets.
The ability to allow small volumes to be striped across lots of disks
could easily outweigh any memory cache performnace issues.
I'm not saying Blake's necessarily wrong here, it's just that like most
interesting questions, the answer is usually "It depends". In this case
it depends on the layout, structure, and usage of the data.
-- Adam Fox
adamfox(a)netapp.com
-----Original Message-----
From: Blake Golliher [mailto:thelastman@gmail.com]
Sent: Monday, June 05, 2006 8:17 PM
To: Fox, Adam; Michael Homa
Cc: toasters(a)mathworks.com
Subject: Re: Suggestions regarding migration from 740 to 270
It's probably not the best idea to go to flexvols on such a small memory
system. Flexvols need use more memory just by it's nature, and will eat
away at your read cache on the 270 (which is already small).
Maybe just to trad vols, and snapmirror? Or if you really needed the
features in flexvols? In that case, this is just an FYI.
-Blake
On 6/5/06, Fox, Adam <Adam.Fox(a)netapp.com> wrote:
> It is possible to preserve snapshots and migrate data, but it's
> tedious at best and unpractical at worst, it just depends on your
> data.
>
> You can use ndmpcopy or qtree SnapMirror (I prefer QSM if you have
it).
> But basically
> you start with the oldest snapshot you want to keep. Migrate that
> snapshot for each qtree you want to migrate (or I suppose you can just
> do the volume if you are doing ndmpcopy).
> Then take a local snapshot on the destination flex vol (probably with
> the same name).
>
> Repeat this process with each snapshot you want to preserve.
> Basically, you are building them from the ground up. It works, but
> like I said, it's tedious for most and impossible for some.
>
> Another alternative for those who don't want to go through this
> process is to just copy the active filesystem over using anything you
> want, then keep the older disks around until they would have been
> deleted anyway. Not sure how that would work with your manual
> snapshots, but some sites with time-based snapshots have found that to
> be more practical, even if a bit inconvient, for a few weeks/months.
>
> Hope this helps.
>
>
> -- Adam Fox
> adamfox(a)netapp.com
>
>
> -----Original Message-----
> From: Michael Homa [mailto:mhoma@uic.edu]
> Sent: Monday, June 05, 2006 3:51 PM
> To: toasters(a)mathworks.com
> Subject: Suggestions regarding migration from 740 to 270
>
> Hi:
>
> Recently, we elected to replace our primary 740 (we have two) with a
> 270.
> The 740, running 6.4.5, has traditional volumes whereas the 270,
> running 7.0.4, has flex volumes. I'm using ndmpcopy to migrate volumes
> from the old box to the new. My question concerns snapshots. I was
> told that I can't use ndmpcopy to migrate the snapshot (if that's not
> true, feel free to tell me). Anyway, we have some user-created
> snapshots that hold important changes. I'm looking for suggestions on
> getting the information contained in the snapshots migrated.
>
> Thanks
>
> Michael Homa
> Operating Systems Support and Database Group Academic Computing and
> Communication Center University of Illinois at Chicago
> email: mhoma(a)uic.edu
>