In one embodiment, the invention provides a method for accessing a physical storage-device array comprising a plurality of storage devices. The method includes (1) obtaining at least one parameter from a profile selected from two or more profiles concurrently defining two or more virtual arrays, each profile defining (i) a different virtual array associated with a corresponding set of storage devices and (ii) a parameter set of one or more parameters used for accessing the virtual array; and (2) generating an instruction, based on the at least one parameter, for accessing, or disallowing access to, information in the virtual array defined by the selected profile, wherein a parameter in each the parameter set defined by each profile indicates whether two or more storage devices in the corresponding virtual array are degraded.