Red Hat OpenShift Administration III: Scaling Deployments in the Enterprise

Pod scheduling is the process of determining in which node to place a pod in the OpenShift cluster.

The OpenShift built-in scheduler identifies the most suitable node for the pods, and its default behavior meets the needs of most OpenShift users.

OpenShift advanced scheduling features enable you to control which node is used for pod placement.

The scheduler profiles control how OpenShift schedules pods on nodes.

Use pod affinity rules to keep sets of pods close to each other, on the same nodes. Pod affinity rules can be preferred or required.

Use pod anti-affinity rules to keep sets of pods far away from each other, on different nodes. Pod anti-affinity rules can be preferred or required.

Use node affinity rules to keep sets of pods running on the same group of nodes. Node affinity rules can be preferred or required.

Use node selectors to schedule pods to a specific set of nodes. You can define node selectors at the pod, project, and cluster-wide levels.

Use taints and tolerations to avoid scheduling pods to a specific set of nodes.

Pod disruption budgets enable you to control the disruption of pods during voluntary disruptions, by specifying the minimum available number of pods simultaneously.