Black lives matter.
We stand in solidarity with the Black community.
Racism is unacceptable.
It conflicts with the core values of the Kubernetes project and our community does not tolerate it.
We stand in solidarity with the Black community.
Racism is unacceptable.
It conflicts with the core values of the Kubernetes project and our community does not tolerate it.
This page shows how to assign a Kubernetes Pod to a particular node using Node Affinity in a Kubernetes cluster.
You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using Minikube, or you can use one of these Kubernetes playgrounds:
Your Kubernetes server must be at or later than version v1.10. To check the version, enterkubectl version
.
List the nodes in your cluster, along with their labels:
kubectl get nodes --show-labels
The output is similar to this:
NAME STATUS ROLES AGE VERSION LABELS
worker0 Ready <none> 1d v1.13.0 ...,kubernetes.io/hostname=worker0
worker1 Ready <none> 1d v1.13.0 ...,kubernetes.io/hostname=worker1
worker2 Ready <none> 1d v1.13.0 ...,kubernetes.io/hostname=worker2
Chose one of your nodes, and add a label to it:
kubectl label nodes <your-node-name> disktype=ssd
where <your-node-name>
is the name of your chosen node.
Verify that your chosen node has a disktype=ssd
label:
kubectl get nodes --show-labels
The output is similar to this:
NAME STATUS ROLES AGE VERSION LABELS
worker0 Ready <none> 1d v1.13.0 ...,disktype=ssd,kubernetes.io/hostname=worker0
worker1 Ready <none> 1d v1.13.0 ...,kubernetes.io/hostname=worker1
worker2 Ready <none> 1d v1.13.0 ...,kubernetes.io/hostname=worker2
In the preceding output, you can see that the worker0
node has a
disktype=ssd
label.
This manifest describes a Pod that has a requiredDuringSchedulingIgnoredDuringExecution
node affinity,disktype: ssd
.
This means that the pod will get scheduled only on a node that has a disktype=ssd
label.
pods/pod-nginx-required-affinity.yaml
|
---|
|
Apply the manifest to create a Pod that is scheduled onto your chosen node:
kubectl apply -f https://k8s.io/examples/pods/pod-nginx-required-affinity.yaml
Verify that the pod is running on your chosen node:
kubectl get pods --output=wide
The output is similar to this:
NAME READY STATUS RESTARTS AGE IP NODE
nginx 1/1 Running 0 13s 10.200.0.4 worker0
This manifest describes a Pod that has a preferredDuringSchedulingIgnoredDuringExecution
node affinity,disktype: ssd
.
This means that the pod will prefer a node that has a disktype=ssd
label.
pods/pod-nginx-preferred-affinity.yaml
|
---|
|
Apply the manifest to create a Pod that is scheduled onto your chosen node:
kubectl apply -f https://k8s.io/examples/pods/pod-nginx-preferred-affinity.yaml
Verify that the pod is running on your chosen node:
kubectl get pods --output=wide
The output is similar to this:
NAME READY STATUS RESTARTS AGE IP NODE
nginx 1/1 Running 0 13s 10.200.0.4 worker0
Learn more about Node Affinity.