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Next: Introduction

The maelstrom: network service debugging via ``ineffective procedures''
Dr. Alva L. Couch, Tufts University,
Noah Daniels, Analog Devices,
(a student at Tufts during this work)
(to appear in Proc. LISA 2001, San Diego, CA)


The process of network debugging is commonly guided by ``decision trees'', that describe and attempt to address the most common failure modes. We show that troubleshooting can be made more effective by converting decision trees into suites of ``convergent'' troubleshooting scripts that do not change network attributes unless these are out of compliance with accepted norms. ``Maelstrom'' is a tool for managing and coordinating execution of these scripts. Maelstrom exploits convergence of individual scripts to dynamically infer an appropriate execution order for the scripts. It accomplishes this in O(n2) procedure trials, where n is the number of troubleshooting scripts. This greatly eases adding scripts to a troubleshooting scheme, and thus makes it easier for people to cooperate in producing more exhaustive and effective troubleshooting schemes.


Alva L. Couch