This chapter showcased how an application is executed over a YARN cluster. The chapter started with explaining the phases involved in the execution flow for an application. These phases explicate the coordination and communication happening between the different YARN components during application execution.
We executed a sample application provided by Hadoop over the YARN cluster. For the sample application, we saw how an application is submitted to the ResourceManager and how YARN executes the containers of the application as a
YarnChild process over the cluster nodes. We also covered progress reports and resource utilization through the ResourceManager web UI.
We also discussed the different failure scenarios and a brief overview about logging in YARN. This chapter was intended to help the users in debugging and analyzing the flow of applications submitted to the cluster.
In the next chapter, we will discuss the internal life cycle management in YARN. It is an extension of the application...