Virtual storage arrays consolidate branch data storage at data centers connected via wide area networks. Virtual storage arrays appear to storage clients as local data storage, but actually store data at the data center. Virtual storage arrays may prioritize storage client and prefetching requests for communication over the WAN and/or SAN based on their associated clients, servers, storage clients, and/or applications. A virtual storage array may transfer large data sets from a data center to a branch location while providing branch location users with immediate access to the data set stored at the data center. Virtual storage arrays may be migrated by disabling a virtual storage array interface at a first branch location and then configuring another branch virtual storage array interface at a second branch location to provide its storage clients with access to storage array data stored at the data center.