Abstract: In a redundant server network system, failover services for a failed server are provided by a survivor server belonging to a common failover group. At startup of a local server process running on the survivor server, a context is created for the local server and for each remote server belonging to the same failover group as the local server. At startup the context of the local server is also activated. The local server process is configured to operate on and make decisions based upon activated contexts. Each context includes server specific configuration and control information. When the survivor server must provide failover services for a failed server belonging to its same failover group, the context corresponding to the failed remote server is activated.

Abstract: The inventive computer system uses a layer of software between the operating system and the hardware that localizes the fail-safe protocols into a single module. The system also uses shared memory allocation functions as the interface with the operating system. The memory allocation function creates data structures to satisfy the requests of the operating system. The system also has a data structure locking mechanism to prevent more than one processor from writing to the data structure at a time. This layer isolates and hides the complexities of the underlying hardware and memory sharing, and presents a simpler view of the hardware as a single system to the operating system that resides above it. Since all of the fail-safe code is in one single module, rather than distributed throughout the operating system, it is easier to test and verify its correct operation, as well as maintain the operating system.

Abstract: Apparatus and method for detecting the presence of macro viruses within a digital computer (1). An application program (5) is associated with the digital computer (1). A global environment (13) is associated with the application program (5). The application program (5) generates at least one local document (11). Macros contained within the global environment (13) and the local document(s) (11) are executed in a simulated manner by an emulator (15). At least one preselected decision criterion is used by a detection module (17) to declare when a macro virus is deemed to be present. Such a criterion is typically the presence of a bidirectional macro, i.e., a macro that copies from a local document (11) to the global environment (13) and vice-versa. Macros deemed to be viruses are preferably deleted by a repair module (19). Additional deletion criteria may include the presence of macros that have the same source name or the same destination name as a bidirectional macro.

Abstract: A first set of test instructions are provided for a first node in a computer network. A corresponding second set is provided for a second node in the network. The test instruction sets are partitioned into modules. The nodes process their respective sets of test instructions independently to generate test results for each module on each node, except when a synchronizing event occurs. Each node stores its test results for each test module. Since the test modules have an ordered processing sequence, each node's test results for corresponding test modules can be compared asynchronously on an ongoing basis.