Cloudera Manager Glossary


A configuration of Cloudera Manager and all the clusters it manages.

dynamic resource pool

A named configuration of resources and a policy for scheduling the resources among YARN applications or Impala queries running in the pool.


A logical entity that contains a set of hosts, a single version of CDH installed on the hosts, and the service and role instances running on the hosts. A host can belong to only one cluster.


A physical or virtual machine that runs role instances.


A physical entity that contains a set of physical hosts typically served by the same switch.


A category of managed functionality, which may be distributed or not, running in a cluster. Sometimes referred to as a service type. For example: MapReduce, HDFS, YARN, Spark, Accumulo. Whereas in traditional environments multiple services run on one host, in distributed systems a service runs on many hosts.

service instance

An instance of a service running on a cluster. A service instance spans many role instances. For example: "HDFS-1" and "yarn".


A category of functionality within a service. For example, the HDFS service has the following roles: NameNode, SecondaryNameNode, DataNode, and Balancer. Sometimes referred to as a role type.

role instance

An instance of a role running on a host. It typically maps to a Unix process. For example: "NameNode-h1" and "DataNode-h1".

role group

A set of configuration properties for a set of role instances.

host template

A set of role groups. When a template is applied to a host, a role instance from each role group is created and assigned to that host.


A role that designates a host that should receive a client configuration for a service when the host does not have any role instances for that service running on it.


A binary distribution format that contains compiled code and meta-information such as a package description, version, and dependencies.

static service pool

A static partitioning of total cluster resources—CPU, memory, and I/O weight—across a set of services.