Abstract: A method of operating a network system may involve receiving data indicating a configuration of components that are included in the network system, detecting a failure of one of the components, computing an availability (e.g., by calculating the instantaneous availability) of the network system from the data in response to detecting the failure, and storing data indicative of the availability of the network system.

Abstract: Provided are a method, system, and program for operating a computer system, wherein the computer includes at least two storage units. A boot routine from an operating system on a first storage unit of the at least two storage units designated as the primary storage unit is executed. A second storage unit of the at least two storage units comprises a spare storage unit, wherein both the storage units maintain copies of the operating system and file system in the computer. If the boot routine does not succeed, then the second storage unit is designated as the primary storage unit, wherein the first storage unit is the spare storage unit after the second storage unit is designated as the primary storage unit. After designating the second storage unit as the primary storage unit, the boot routine is executed from an operating system on the second storage unit designated as the primary storage unit.

Abstract: A method of operating a network system may involve receiving data indicating a configuration of components that are included in the network system, detecting a failure of one of the components, computing an availability (e.g., by calculating the instantaneous availability) of the network system from the data in response to detecting the failure, and storing data indicative of the availability of the network system.

Abstract: A magnetic disc cartridge includes two sets of opposing ribs arranged on opposite sides of the cartridge so that each rib of one set of ribs is skew with respect to each rib of the other set of ribs. The ribs exert pressure on both sides of a rotating medium via wiper elements, which sandwich the medium, so as to clean debris from both sides of the medium while maintaining medium planarity in a region defined between the two sets of opposing ribs. Optionally, each rib of the one set of ribs may cross perpendicularly with respect to each rib of the other of the sets of ribs.