You configure Hadoop cluster with both MapReduce frameworks, MapReduce v1 (MRv1) and

MapReduce v2 (MRv2/YARN). Which two MapReduce (computational) daemons do you need to
configure to run on your master nodes?

A.
JobTracker

B.
ResourceManager

C.
ApplicationMaster

D.
JournalNode

E.
NodeManager

Explanation:
MapReduce has undergone a complete overhaul in hadoop-0.23 and we now have,
what we call, MapReduce 2.0 (MRv2) or YARN.
The fundamental idea of MRv2 is to split up the two major functionalities of the JobTracker,
resource management and job scheduling/monitoring, into separate daemons. The idea is to have
a global ResourceManager (RM) and per-application ApplicationMaster (AM). An application is
either a single job in the classical sense of Map-Reduce jobs or a DAG of jobs.
The ResourceManager and per-node slave, the NodeManager (NM), form the data-computation
framework. The ResourceManager is the ultimate authority that arbitrates resources among all the
applications in the system.
The per-application ApplicationMaster is, in effect, a framework specific library and is tasked with
negotiating resources from the ResourceManager and working with the NodeManager(s) to
execute and monitor the tasks.
Note:
* MRV2 maintains API compatibility with previous stable release (hadoop-0.20.205). This means
that all Map-Reduce jobs should still run unchanged on top of MRv2 with just a recompile.
Reference:
Apache Hadoop NextGen MapReduce (YARN)