Cheers Phil - thanks for taking the time to reply.
The EMC Clarion sounds complicated - none of that is made clear in their spiel about the CX300 / 320 series but from what I can gather they seem to have got their iSCSI act together wrt the controllers natively handling things.
We'll probably be sticking with iSCSI - FC infrastructure sounds really expensive as it starts to grow in size.
Thanks again,
Raj.
On 11/22/06,
Phil Pennock <na-toasters-phil@spodhuis.org> wrote:
On 2006-11-22 at 08:40 +1300, Raj Patel wrote:
> At the moment the NetApp is the most familiar to me as I have used one of
> their NAS boxes before and the simulator provides a pretty good indication
> of how it works. However the iSCSI seems a bit of a 'bolt-on' and its not
> clear if it will handle tiered storage as well as the other vendors (then
> again does it matter?).
>
> The HDS & EMC are unknown quantities (other than what I can glean from the
> web).
When I looked about a year ago, the EMC Clariions (sp?) didn't directly
handle iSCSI; instead, you use a Celerra NAS head which also provides
iSCSI. This means that if you provision an iSCSI LUN, it exists as an
item in a filesystem which lives in a native LUN dedicated to the NAS
unit and the EMC CX box has no separate visibility of it. It's an
either/or proposition. Your migration path is to have enough storage to
allocate a new native LUN and migrate the data via the clients. This
was a CX500, if memory serves.
With the NetApp kit, the NetApp folks were very clear that an iSCSI LUN
is visible where you configure it to be visible and if you want to
switch from iSCSI to fibre channel then it was a matter of changing the
configured interfaces; the LUN remained visible with the same content.
I never really tested the NetApp iSCSI functionality though, but I'm
strongly inclined to believe NetApp that this migration works -- it's
consistent with what I understand of the design.
-Phil