Cisco Nexus 7000 Design Manual page 21

Data ONTAP operating in 7-Mode is deployed on an HA pair of controllers that is discrete from any
other storage systems in the environment and is managed as such. For this reason, the scalability with
clustered Data ONTAP is superior to that of 7-Mode, which is further discussed in
ONTAP" section on page
Clustered Data ONTAP
With the release of clustered Data ONTAP 8.1, NetApp introduces enterprise-ready, unified scale-out
storage. Clustered Data ONTAP is the basis for large virtualized shared storage infrastructures that are
architected for nondisruptive operations over the system lifetime. Controller nodes are deployed in HA
pairs, with these HA pairs participating in a single storage domain or cluster.
Data ONTAP scale-out is a way to respond to growth in a storage environment. All storage controllers
have physical limits to their expandability: number of CPUs, memory slots, and space for disk shelves
that dictate the maximum capacity and controller performance. If more storage or performance capacity
is needed, it might be possible to add CPUs and memory or install additional disk shelves, but ultimately
the controller becomes completely populated, with no further expansion possible. At this stage the only
option is to acquire another controller. One way to do this is to "scale up": that is, to add additional
controllers in such a way that each is a completely independent management entity that does not provide
any shared storage resources. If the original controller is to be completely replaced by the newer and
larger controller, data migration is required to transfer the data from the old controller to the new one.
This is time-consuming and potentially disruptive and most likely requires configuration changes on all
of the attached host systems.
If the newer controller can coexist with the original controller, there are now two storage controllers to
be individually managed, and there are no native tools to balance or reassign workloads across them. The
situation becomes worse as the number of controllers increases. If the scale-up approach is used, the
operational burden increases consistently as the environment grows, and the end result is a very
unbalanced and difficult-to-manage environment. Technology refresh cycles require substantial
planning in advance, lengthy outages, and configuration changes, which introduce risk into the system.
By contrast, using scale-out means that as the storage environment grows, additional controllers are
added seamlessly to the resource pool residing on a shared storage infrastructure. Host and client
connections as well as datastores can move seamlessly and nondisruptively anywhere in the resource
pool, so that existing workloads can be easily balanced over the available resources, and new workloads
can be easily deployed. Technology refreshes (replacing disk shelves, adding or completely replacing
storage controllers) are accomplished while the environment remains online and continues serving data.
Although scale-out products have been available for some time, these were typically subject to one or
more of the following shortcomings:
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•
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Therefore, while these products are well positioned for certain specialized workloads, they are less
flexible, less capable, and not robust enough for broad deployment throughout the enterprise.
Data ONTAP is the first product to offer a complete scale-out solution, and it offers an adaptable,
always-available storage infrastructure for today's highly virtualized environment.
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Limited protocol support (NAS only)
Limited hardware support (supports only a particular type of storage controller or a very limited set)
Little or no storage efficiency (thin provisioning, deduplication, compression)
Little or no data replication capability
VMware vSphere 5.1 on FlexPod with Nexus 7000 Using FCoE
FlexPod Design Details
"Clustered Data
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