Cluster behavior

Provides the relevance between Network Performance Insight® and its related services with the node behavior in a cluster.

Network Performance Insight supports the following types of node behavior.
Cluster singleton
A clustered singleton service (also known as an HA singleton) is a service that is deployed on multiple nodes in a cluster, but is providing its service on only one of the nodes. The node that is running the singleton service is typically called the oldest node.
Load balancing
Load balancing improves the distribution of workloads across multiple nodes where each of the node serves different set of clients that are mutually exclusive.
Managed load balancing
The difference between Load Balancing with Managed load balancing here is that, node acts as manager node to monitor the load balancing activities. The manager node monitors and distributes the workload among the active nodes.
Data replication
A replication strategy determines the nodes where data replicas are placed. The replicas on multiple nodes are stored to ensure reliability and fault tolerance.
Monitoring in each node
A service that is installed on each node in a cluster, where it monitors and provides information on the installed nodes.
Single instance
A service that is installed on a single node in a cluster, which provides its service across all nodes.
The following table lists the service components and their node behavior. Use the following information as guidance to set up your environment.
Table 1. Cluster node behavior
Services Service Type Service Components Cluster node behavior
Network Performance Insight Master Manager Monitoring on each node
Slave DNS Cluster singleton
Slave Cacti Collector Managed load balancing
Slave Event Cluster singleton
Slave Exporter Cluster singleton
Slave Flow Analytics Managed load balancing
Slave Flow Collector Load balancing

For more information, see Configuring the number of interfaces.

Slave SNMP Discovery Cluster singleton
Slave Tivoli Network Manager Collector Cluster singleton
Slave Storage Cluster singleton
Slave Threshold Managed load balancing
Slave Timeseries Data replication
Slave UI Load balancing

For more information, see UI

Slave SNMP Collector Manual load balancing (defined by snmp scoping)
Slave Formula Service Manual load balancing (defined by snmp scoping)
HDFS Master NameNode Single instance
Master SNameNode Single instance
Slave DataNode Data replication
YARN Master Timeline Server Single instance
Master Resource Manager Single instance
Slave Node Manager Managed load balancing
ZooKeeper Master ZooKeeper Data replication
Ambari Metrics Master Collector Single instance
Slave Monitor Monitoring on each node
Kafka Master Kafka Broker Data replication
Master Kafka Connect Single instance
Master Kafka Schema Registry Load balancing
MapReduce2 Master History Server Single instance