148422597X Kubernetes Management Design Patterns [Vohra 2017-01-29] {E559F6BB}

Chapter 9 ■ Scheduling Pods on Nodes
Next, we shall demonstrate that if multiple pods have matching labels, one of the nodes is used. Label
the third node with the same label as one of the other nodes:
kubectl label nodes ip-10-0-0-153.ec2.internal kubernetes.io/image-name=hello-world
The third node is also labeled, as shown in Figure 9-25.
Figure 9-25. Labeling a third node
Listing the node labels should display two nodes with the common label kubernetes.io/imagename=hello-world,
as shown in Figure 9-26.
Figure 9-26. Two nodes with the same label
Delete the pod hello-world with kubectl, as next we shall create the pod again to find which node is
the pod scheduled on, given two nodes with the same label as in the nodeSelector field. Create the helloworld
pod again using the same definition file. List the pod, and it should be shown on one of the two nodes
that have the label kubernetes.io/image-name=hello-world, which are ip-10-0-0-152.ec2.internal
and ip-10-0-0-153.ec2.internal. The pod is scheduled on the first node it finds with the matching label,
which is ip-10-0-0-152.ec2.internal as shown in Figure 9-27.
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