The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 22, 2007
Filed:
Sep. 18, 2001
Arthur L. Zaifman, Marblehead, MA (US);
Stephen J. Ciavaglia, Merrimack, NH (US);
Arthur L. Zaifman, Marblehead, MA (US);
Stephen J. Ciavaglia, Merrimack, NH (US);
Enterasys Networks, Inc., Andover, MA (US);
Abstract
A hierarchical, distributed Availability Management (AM) process for recovering from component failures in a data processing system. The hierarchy of AM elements track a failure modality hierarchy of the data processing system components. For example, the system hierarchy may include system cards, processors, and processes, in which case the associated AM elements may be implemented at a card manager (CM) level, a system manager (SM) level, and a process manager (PM) level. The AM hierarchy is designed to achieve a failure granularity so that failures in the lower levels of the hierarchy have less of an impact on the entire system. Each AM element is responsible for receiving failure notifications from processing system components associated with a next lower level of the hierarchy. Upon such indication, if the AM element determines that the failed component may be restarted, if the failed component may be restarted, the AM element then determines if it can be hot, warm, or cold restarted and it does so without further notification or implication to system availability of other components. Hot restart requires complete integrity of sate information, warm restart causes a recovery of last known good state information, and a cold restart results in the re-initialization of state information. If, the component cannot be restarted, then notification is provided to the next higher level of the hierarchy and the AM element itself terminates. One of the AM processes may execute as an identity management protocol. The identity protocol sets a temporary master state; waits a predetermined amount of time; and then sets a final master state only if no other system card has asserted a temporary master state. The waiting time period is selected to be greater than the longest expected initialization process for peer components in the system.