kubectl taint

• Offer restrictions to what pods can be scheduled on which node
• The master nodes are automatically tainted! That prevents any pods to be scheduled there

Taint & Toleration

• Taint: repeal to a specific pod. It's applied to the node
• Toleration: tolerance that a pod has to a specific node taint. If not specified, pods have no tolerations. Toleration does not guarantee that a pod will be scheduled to the tolerated pod

Taint Effects

• 3 Taint Effects
• NoSchedule: pods cannot be scheduled on the node
• PreferNoSchedule: pods are avoided scheduling on this node
• NoExecute: new pods will not be scheduled on this node, existing pods will be evicted on this node (it will be killed soon and recreated in another node)

# Apply taints to a node
kubectl taint "no" "node-name" \
  "app=blue:NoSchedule"

kubectl taint "no" "node-name" \
  "app=value:PreferNoSchedule"

kubectl taint "no" "node-name" \
  "app=blue:NoExecute"

# Remove taint
kubectl taint "no" "node-name" \
  "node-role.kubernetes.io/master:NoSchedule"-