About root cause analysis
Within Network Manager, the term root cause analysis is used to refer to topological root cause analysis. Topological root cause analysis means that, in a situation where there are multiple events, Network Manager uses knowledge of the network topology to establish a point of failure and to identify those events that are symptomatic.
A failure on the network usually generates multiple alerts. This is because a failure condition on one device may render other devices inaccessible. Alerts are generated indicating that all of these devices are inaccessible.
Network Manager performs root cause analysis by correlating event information with topology information, and thereby determining which devices are temporarily inaccessible due to other network failures.
Alerts on devices which are temporarily inaccessible are suppressed, that is, shown as symptoms of the original, root cause alert. Root-cause alerts are shown in alert lists and topology maps with the highest severity so that operators can easily identify them.
Root cause is implemented using a series of root cause analysis rules. These rules are enabled by default. No manual configuration is required.