2.3. Node types

Master

These nodes run processes that expose the Kubernetes API, watch and schedule newly created pods, maintain node health and quantity, and control interaction with underlying cloud providers.

Infrastructure (Infra)

Infra nodes run cluster level infrastructure services such as logging, metrics, registry, and routing. These are optional in OpenShift Container Platform clusters. In order to separate OpenShift Data Foundation layer workload from applications, ensure that you use infra nodes for OpenShift Data Foundation in virtualized and cloud environments.

To create Infra nodes, you can provision new nodes labeled as infra. For more information, see How to use dedicated worker nodes for Red Hat OpenShift Data Foundation

Worker

Worker nodes are also known as application nodes since they run applications.

When OpenShift Data Foundation is deployed in internal mode, you require a minimal cluster of 3 worker nodes. Make sure that the nodes are spread across 3 different racks, or availability zones, to ensure availability. In order for OpenShift Data Foundation to run on worker nodes, you need to attach the local storage devices, or portable storage devices to the worker nodes dynamically.

When OpenShift Data Foundation is deployed in external mode, it runs on multiple nodes. This allows Kubernetes to reschedule on the available nodes in case of a failure.