Cloud Computing and SOA Convergence in Your Enterprise: A Step ...

Governance for the Clouds 151
Figure 8.4 Dependencies among applications and services mean that when services
fail or are changed, they bring down other services that are coupled to the
failed or changed service.
quickly diminishes the value of cloud computing. The use of service governance
approaches and technology mitigates the risks.
Operational monitoring means that we place controls around the services
through the use of policies, and we can monitor the services, onpremise
or cloud delivered, during runtime. What’s core here is that you understand
what needs to be monitored and at what granularity.
Since there is a performance impact of service monitoring, it is important
that you monitor only those services that are critical to the operations of
the business. You must make sure they are up and running, and that they
provide the performance required by the other services and applications that
leverage them. Keep in mind that the overall system runs only as fast as the
slowest component.
Monitoring services can be a bit tricky within a cloud computing offering,
since you typically do not own the services or the monitoring interfaces
to those services. What the cloud computing provider exposes to you is what
you get. While providers may allow you to leverage their “monitoring console,”
you may not be able to monitor their systems down to the service level.
You need to consider that limitation as you select a cloud computing provider,
making sure you have the ability to monitor those services and can
monitor them at the proper level of granularity.