The kafka and zookeeper services are required for sending data to and from the Spark cluster.
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See 5.2 Preparing and Creating Scripts for KPI Management on how to startup Spark, Kafka and zookeeper.
The topics are for transferring data to the Spark Application, receiving calculated KPIs from Spark and a third topic for alarms. The default names of the topics are kpi-input, kpi-output and kpi-alarm, but the names can be altered in the KPI Management Profile. Please note that the number of partitions must match the number of Kafka brokers
Retention Settings
The default data retention period in Kafka is one day. You can change the length of this period to conserve disk space.
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