Abstract: The present invention extends to methods, systems, and computer program products for extending non-volatile storage at a computer system. In some embodiments, a file operation is performed on at least one shadow copy of a file that is perceived by an application to be stored on a single volume. A plurality of shadow copies of a file can be accessed using durable file identifiers that are durable across changes to other file characteristics. It is indicated back to the application that the file operation was performed on the file perceived to be stored on the single volume. Storage capabilities are enhanced through migration and/or replication of files to newly added volumes.

Abstract: The present invention extends to methods, systems, and computer program products for extending non-volatile storage at a computer system. In some embodiments, a file operation is performed on at least one shadow copy of a file that is perceived by an application to be stored on a single volume. A plurality of shadow copies of a file can be accessed using durable file identifiers that are durable across changes to other file characteristics. It is indicated back to the application that the file operation was performed on the file perceived to be stored on the single volume. Storage capabilities are enhanced through migration and/or replication of files to newly added volumes.

Abstract: Failover of servers over which data is partitioned is disclosed. A first server services client requests for data of a first type, a second server services client requests for data of a second type, and so on. A master server manages notifications from clients and servers as to indication that one of the servers is offline. When the master server receives such a notification, it verifies that the indicated server is in fact offline. If the server is offline, then the master server so notifies the other server. When the first server is offline, one of the other servers may become the failover server, processing client requests for data usually processed by the first server.