Scaling down a NiFi cluster
You can also remove nodes from your NiFi cluster for cost optimization. For example, scale down the NiFi cluster when there is less data to be processed in order to save infrastructure costs.
- Log into CDP Public Cloud UI.
- Go to .
Select the datahub cluster where your NiFi flow is running.
Before scaling down you can go to the NiFi UI by clicking NiFi to check the current number of NiFi nodes you have in your NiFi cluster, as shown in the following image:
Click Actions, and select
The Cluster Resize window appears.
Select your hostgroup from the dropdown, decrease the number of nodes by
clicking the - icon, and then click
It takes some time for the change to take place. In the background, the following processes occur:
You can go to the NiFi UI to check that the nodes are successfully removed from the NiFi cluster:The scale down event is complete only after the nodes are no longer listed in the Hardware tab of the Data Hub Clusters page, as shown in the following image:
- The nodes to be removed are disconnected from the NiFi cluster.
- Processing of data on these nodes is stopped.
- The data located on the nodes to be removed are moved to the remaining nodes of the cluster. This ensures no data loss during a scale down event.
- The NiFi service is stopped on these nodes
- The underlying virtual machines are stopped and deleted.
Restart the NiFi and NiFi Registry services from the Cloudera Manager UI after
the nodes are removed.
Go to the Cloudera Manager UI by clicking the
The Cloudera Manager UI appears.
- Restart both NiFi and NiFi Registry services.
- Go to the Cloudera Manager UI by clicking the CM-UI link.