Quoting from the NetApp official announcement:

Network Appliance, Inc., a leading provider of storage and data management solutions, announced today that it has strengthened its relationship with VMware, the global leader in software for industry-standard virtualized desktops and servers, to collaborate on joint engineering, marketing, service, and support.

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The NetApp-VMware relationship is designed to enable the two companies to work on joint engineering solutions for advanced application mobility, backup and recovery, and disaster recovery.

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NetApp and VMware joint engineering projects are also targeted at further simplifying disaster recovery, streamlining test and development environments, optimizing storage utilization of virtual desktop consolidations, and ultimately creating a tightly integrated server-to-storage virtualization solution that makes next-generation data management real and affordable for the enterprise…

NetApp cooperation with VMware on disaster recovery is not too surprising, now that VMware admitted it’s working on a disaster recovery solution.