Root-cause
analysis
performs root-cause analysis at the different layers of the managed network, as
shown in
Bottom-up root-cause analysis
.
Bottom-up
root-cause analysis

A fundamental principle of
root-cause analysis in
or
any other
VMware Smart Assurance
Domain Manager
is the bottom-up approach, from physical-transport layer to application layer.
Problems that occur at lower levels impact objects at higher levels.
performs availability-based root-cause analysis of the
discovered MPLS and VPN topology objects, and relates physical-transport problems or BGP
problems to the MPLS and VPN objects, along the affected data path, that are no longer
accessible or experience from lack of response or performance as a result of the
physical-transport or BGP problems.
When
detects an MPLS alarm, it checks for any physical-transport problem from
IP Availability Manager
or any BGP problem from
that might be causing the alarm. If it finds such a problem,
diagnoses the MPLS alarm as a symptom and exports the underlying
physical-transport or BGP problem and the symptom to the
Global Manager
,
as explained in
Chapter 4, “MPLS Cross-Domain Impact
Correlation Analysis.”If it does not find such a
problem,
focuses its analysis on the MPLS domain and performs the root-cause analysis
that is described in this chapter.