Understanding Deployments and Replica Sets in Kubernetes | Scribe

    Understanding Deployments and Replica Sets in Kubernetes

    • Hafeez Baig |
    • 17 steps |
    • 2 minutes
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    Please review the previous lab on Pods in Kubernetes before proceeding with this lab. <https://scribehow.com/shared/Understanding_Pods_in_Kubernetes__kJVQfpjbRUGzsxQRyaK-rA>
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    On the **Cloud Shell CLI**, type the command [[kubectl set image deplyment hello-world-rest-api hello-world-rest-api=in28min/hello-world-rest-api:0.0.2.RELEASE]]
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    **What is [[kubectl set image deplyment hello-world-rest-api hello-world-rest-api=in28min/hello-world-rest-api:0.0.2.RELEASE ]]command?**\ \ The command `kubectl set image deployment hello-world-rest-api hello-world-rest-api=in28min/hello-world-rest-api:0.0.2.RELEASE` updates the image used by the `hello-world-rest-api` container in the `hello-world-rest-api` Deployment to the new version `in28min/hello-world-rest-api:0.0.2.RELEASE`. This triggers a rolling update, where Pods are gradually replaced with new ones using the specified image version, ensuring zero downtime for the application.
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    **deployment.apps/hello-world-rest-api image updated** is displayed
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    Go back to the **hello-world** tab
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    **Hello World V1 hpknq** is displayed
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    On the top left corner click on the page reload button
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    **Hello World V2 72fk4** is displayed **Note:** You can view that now the Version is updated to V2
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    To get replicas, type the command [[kubectl get replicasets]]
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    **What is command** [[kubectl get replicasets]]**?**\ \ The `kubectl get replicasets` command lists all ReplicaSets in your Kubernetes cluster, showing their status and the number of desired, current, and ready replicas.
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    Information of the replicasets is displayed
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    **What are replicasets in GCP?** ReplicaSets in Google Cloud Platform (GCP) are a Kubernetes object used to ensure a specified number of pod replicas are running at any given time. They play a crucial role in maintaining the desired state of your application by monitoring and managing pod instances.
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    To get **Pods**, type the command [[kubectl get pods]]
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    **What is the command** [[kubectl get pods]]**?**\ \ The `kubectl get pods` command is used to list all pods in your Kubernetes cluster, showing their status, namespaces, and other relevant details.
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    Copy the Name **hello-world-rest-api-5df8fb76f9-a5w27**
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    To delete the Pod, type the command [[kubectl delete pod &lt;paste the pod name here&gt;]]
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    **What is** [[kubectl delete pod hello-world-rest-api-5df8fb76f9-a5w27 ]]**command?**\ \ The `kubectl delete pod hello-world-rest-api-5df8fb76f9-a5w27` the command deletes the specified pod (`hello-world-rest-api-5df8fb76f9-a5w27`) from your Kubernetes cluster.
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    **pod "hello-world-rest-api-5df8fb76f9-a5w27" deleted** is displayed
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    Congratulations you have successfully deleted the pod!
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    To get the Pods, type the command [[kubectl get pods]] **Note:** You can see that a new pod has been created