Background
Event Diagnosis is the next step after Event Detection. IEPM group has established a large infrastruture for network performance measurment all over the world. This infrasture provides near real time network performance related data. IEPM group has developed analysis techniques and tools that detect drop in performance. Event Diagnosis project is aimed at finding out the cause of performance drop. So it is a sub-system under IEPM-BW being developed over Event Detection. Current work is being carried out by a team of researchers at SLAC but given the nature and evident benfits of project it is expected to expand quickly.
Implementation Details
IEPM infrastructure consists of Monitoring Nodes and Monitored Nodes. For Event Diagnosis pupose we add another term Central Node. Below is a small description of each type of node.
Monitoring Node: A node that runs tools for network measurment, collects data, stores data, analyzes data for Event Detection and generates alert on the basis of analysis result. Currently we have six such nodes.
Monitored Node: A node that is measured by a Monitoring Node. Each Monitoring Node has its own set of Monitored Nodes. Currently we have about 40 monitored nodes all over the world.
Central Node: A node that runs Event Diagnosis analysis. There is only one such node for the time being (SLAC)
All the implementation is in the form of perl scripts or cgi/perl scripts. Some scripts reside on monitoring nodes and some on central node. There is no script currently on any monitored node.
Code on Monitoring Nodes: Every monitoring node has three cgi scripts.
nodeid_host.cgi: if script is called with option n, should be provided with node id. if script is called with option h, should beprovide ipv4 host alias. In either case it return complete record from which one can deduce node id or ipv4 host alias.
alert_rec.cgi: if called with out any option, returns all vailable alerts present on monitoring node other wise returns only th alerts which fulfill tyhe criteria
tracert_analysis.cgi: provided with time frame and
Code on Central Node: