Smarts SAM/IP: How is the "Certainty" field calculated for Smarts SAM and Smarts IP events?

Products

• VMware

Environment

VMware Smart Assurance - SMARTS

Resolution

How is the Certainty field calculated for Smarts SAM and Smarts IP events?
Is it possible to have a Certainty value of less than 100% for a Smarts root cause event?

Every problem in Smarts is declared with a set of symptoms. Depending on how many symptoms are active for a problem, the Smarts codebook calculates a Certainty value. The Certainty calculation also depends on the shared symptoms between the problems.

Smarts uses a complex algorithm that governs the calculation in which it essentially answers the following questions:

1. Which problems are relevant to be diagnosed?
    
2. • Router Unresponsive
   • MightBeDown 
   • PeerDownorFlapping
   • Neighboring system down or Flapping
     
      
3. What is the minimal set of symptoms that these problems cause?
4. What is Apriori Probability? (Apriori is a classic algorithm for learning association rules).