Abstract: An architecture provides the ability to create and maintain multiple instances of virtual servers, such as virtual filers (vfilers), within a server, such as a storage appliance. A vfiler is a logical partitioning of network and storage resources of the storage appliance platform to establish an instance of a multi-protocol server. Each vfiler is allocated a subset of dedicated units of storage resources, such as volumes or logical sub-volumes (qtrees), and one or more network address resources. Each vfiler is also allowed shared access to a file system resource of a storage operating system. To ensure controlled access to the allocated and shared resources, each vfiler is further assigned its own security domain for each access protocol. A vfiler boundary check is performed by the file system to verify that a current vfiler is allowed to access certain storage resources for a requested file stored on the filer platform.

Abstract: Techniques introduced here swap logical unit meta-data of a logical unit without offlining the logical unit. In accordance with the techniques, a connection between a network storage controller and a host for the logical unit is maintained while meta-data of the logical unit are swapped with another logical unit available to the network storage controller. The swapping substitutes one logical unit for another without disconnecting the host. Advantageously, the host is not required to perform operations to re-establish a connection. Various software and hardware units can implement the techniques described herein.

Abstract: An architecture provides the ability to create and maintain multiple instances of virtual servers, such as virtual filers (vfilers), within a server, such as a storage appliance. A vfiler is a logical partitioning of network and storage resources of the storage appliance platform to establish an instance of a multi-protocol server. Each vfiler is allocated a subset of dedicated units of storage resources, such as volumes or logical sub-volumes (qtrees), and one or more network address resources. Each vfiler is also allowed shared access to a file system resource of a storage operating system. To ensure controlled access to the allocated and shared resources, each vfiler is further assigned its own security domain for each access protocol. A vfiler boundary check is performed by the file system to verify that a current vfiler is allowed to access certain storage resources for a requested file stored on the filer platform.

Abstract: In a remote mirroring system, device, and method, a master storage unit stores information in a log and uses the information from the log to quickly resynchronize slave images following a failure in the master storage unit. Upon receiving a write request from a host, the master storage unit stores a write entry in the log. The write entry includes information that identifies a portion of the slave images that may be unsychronized from the master image due to the write request. The master storage unit then proceeds to update the master image and the slave images. The log is preserved through the failure, such that the log is available to the master storage unit upon recovery from the failure. When the master storage unit is operational following the failure, the master storage unit resynchronizes the slave images to the master image by copying those portions of the master image indicated in the log to the slave images.