Kubernetes - Taints and Tolerations

taints and tolerations tend to set restrictions on what pods can be scheduled on a node.

taints are set on nodes

to add taint to a node you need to execute the following command kubectl taint nodes node-name key=value:taint-effect

There are three taint effect

• NoSchedule ⇒ prevent pods from being scheduled on the node
• PreferNoSchedule ⇒ avoiding pods to be scheduled on the node
• NoExecute ⇒ new pods will not be scheduled on the node and existing pods on the node if any will be evicted if they do not tolerate the taint.

toleration are set on pods

to add toleration on a pod you need to update the node definition file and in the spec section we will need to add a toleration section and move the same values that used to create the taints to definitions example would be

 
	toleration:
		-key: app
		operator: "Equal"
		value: "blue"
		effect: "NoSchedule"