Scheduling

Node Selector

Node affinity is a property of Pods that attracts them to a set of nodes (either as a preference or a hard requirement)

kubectl label nodes node1 job=ai-training
kubectl label nodes node1 job=render-3d

Pod configuration

apiVersion: apps/v1
kind: Deployment
metadata:
  name: hello-k8s
spec:
  replicas: 3
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 2
      maxSurge: 2
  selector:
    matchLabels:
      app: hello-k8s
  template:
    metadata:
      labels:
        app: hello-k8s
    spec:
      containers:
        - name: hello-k8s
          image: CONTAINER_IMAGE
          ports:
            - containerPort: 80
      nodeSelector:
        job: ai-training

Taints and tolerations

Taints are the opposite -- they allow a node to repel a set of pods.

Tolerations are applied to pods, and allow (but do not require) the pods to schedule onto nodes with matching taints.

Taints and tolerations work together to ensure that pods are not scheduled onto inappropriate nodes. One or more taints are applied to a node; this marks that the node should not accept any pods that do not tolerate the taints.

Affinity / Anti-Affinity

It still can schedule pods even if there`s a anti-affinity.