Chapter 4: Creating a Kubernetes Cluster

Activity 4: Migrating a Running Application in Kubernetes Cluster

Solution:

Perform the following steps to complete this activity:

1. Run a sample web application with six replicas in the cluster:

   kubectl run hello-world --image=gcr.io/google-samples/hello-app:1.0 --replicas=6

   Figure 4.30: Creating hello-world application

2. Check the status of pods of the sample web application and their nodes:

   kubectl get pods -o wide

   Figure 4.31: Pods and their nodes of the hello-world application

3. Create a node pool in GCP with a larger memory:

   gcloud container node-pools create high-memory-pool --cluster=devops \
     --machine-type=n1-highmem-2 --num-nodes=2

   

   Figure 4.32: Node pool creation

4. Wait until all nodes are Ready in the cluster:

   kubectl get nodes --label-columns=beta.kubernetes.io/instance-type

   Figure 4.33: Kubernetes nodes after pool creation

5. Mark the nodes in the default node pool as unschedulable and make Kubernetes move the workloads...