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File-system virtualization product sampler
File-system virtualization products are offered by a number of vendors, each coming from a different background with varying objectives.
AutoVirt File Virtualization software: Like Microsoft DFS, AutoVirt is a software-only product that runs on Windows servers.
The AutoVirt global namespace uses the CIFS protocol to interact with file servers, clients and DNS. When a client requests a file, DNS facilitates resolution to the appropriate storage device. The global namespace acts as an intermediary between client and DNS. With the AutoVirt global namespace in place, client shortcuts refer to the namespace. The namespace is the authority on the location of networked files and provides the final storage referral with the help of DNS.
AutoVirt can be introduced nondisruptively to clients, without the need to make any changes on clients, by populating the AutoVirt namespace server with the shares of existing file stores. Although it can be done manually, a data discovery service automates discovery of existing file stores and populates the AutoVirt namespace server with metadata. This differs from Microsoft DFS, which requires clients to be configured with the new DFS shares, rather than continuing to use existing file shares.
Also contrary to Microsoft DFS, AutoVirt provides a policy engine that enables rule-based data mobility across the environment to migrate, consolidate, replicate
EMC Rainfinity file virtualization appliance: Rainfinity is a family of file-system virtualization products that virtualize access to unstructured data, and provide data mobility and file tiering services. The Rainfinity Global Namespace Appliance provides a single mount point for clients and applications; the Rainfinity File Management Appliance delivers policy-based management to automate relocation of files to different storage tiers; and the Rainfinity File Virtualization Appliance provides nondisruptive data movement.
Contrary to F5's ARX, the Rainfinity File Virtualization Appliance architecture is designed to switch between in-band and out-of-band operations as needed. The appliance is out-of-band most of the time, and data flows between client systems and back-end file stores directly. It sits outside the data path until a migration is required and then switches to in-band operation.
F5 ARX Series: Acquired from Acopia in 2007 and rebranded as F5 ARX, the F5 ARX series is an inline file-system virtualization appliance. Usually deployed as an active-passive cluster, its located between CIFS/NFS clients and heterogeneous CIFS/NFS file stores, presenting virtualized CIFS and NFS file systems to clients. Unstructured data is presented in a global virtualized namespace. Built like a network switch, it's available with 2 Gbps ports (ARX500), 12 Gbps ports (ARX2000) and 12 Gbps ports plus two 10 Gbps ports (ARX4000).
This was first published in September 2010