Kubernetes - Creating Namespaces

Kubernetes namespaces provide a way to divide cluster resources between multiple users, teams, or applications. By isolating different environments (like dev, test, and prod) within the same cluster, namespaces help in organizing and managing resources efficiently.

By default, Kubernetes comes with four namespaces: default,kube-public, kube-system and kube-node-lease

Understanding Kubernetes Namespaces

When you first deploy a Kubernetes cluster, it comes with four default namespaces:

default: The default namespace for resources with no other specified namespace.
kube-public: Used for resources that should be publicly accessible across the cluster. Typically contains cluster-wide information.
kube-system: Reserved for Kubernetes system components, such as the API server, scheduler, and other core processes.
kube-node-lease: Used for managing node lease objects, which help in determining the availability of nodes in the cluster.

These namespaces allow you to categorize and manage resources efficiently, especially as your cluster grows in complexity.

Creating a Kubernetes Namespace

Creating a namespace in Kubernetes is a straight forward process. You can use the kubectl command-line tool or a YAML file.

1. Verifying Existing Namespaces

Before creating a new namespace, it's helpful to verify the namespaces already running in your cluster:

kubectl get namespaces

2. Creating a Namespace Using `kubectl create` Command (Imperative Approach)

The simplest way to create a namespace is by using the kubectl create command:

kubectl create namespace <namespace-name>

For example, to create a namespace called dev:

kubectl create namespace dev

You can verify the creation by listing all namespaces:

kubectl get namespaces

3. Creating a Namespace Using a YAML Configuration (Declarative Approach)

Create a YAML file named namespaces.yaml:

apiVersion: v1
kind: Namespace
metadata:
  name: test

Apply the YAML file to create the namespace:

kubectl apply -f namespaces.yaml

This declarative method is ideal for maintaining version control and automating your Kubernetes infrastructure.

Verifying the Namespace

After creating a namespace, you can verify its existence with:

kubectl get namespaces

This command will list all namespaces in your cluster, including the newly created one.

Deleting a Kubernetes Namespace

Deleting a namespace is just as simple as creating one, but you need to be cautious. When you delete a namespace, all resources (like pods, services, and deployments) within that namespace are also deleted.

To delete a namespace, use the following command:

kubectl delete namespace <namespace-name>

For example, to delete the dev namespace:

kubectl delete namespace dev

This will remove the namespace and all its resources from your cluster.

Conclusion

Namespaces are a powerful feature in Kubernetes that allows for efficient resource management and isolation within a cluster. By understanding how to create and delete namespaces, you can better organize your workloads and maintain a clean and manageable cluster environment.

Kubernetes - Creating Namespaces

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2. Creating a Namespace Using `kubectl create` Command (Imperative Approach)

3. Creating a Namespace Using a YAML Configuration (Declarative Approach)

Conclusion

Command Palette

Comments

DevOps

Kubernetes - ReplicaSet & DaemonSet

More from this blog

2. Creating a Namespace Using kubectl create Command (Imperative Approach)

3. Creating a Namespace Using a YAML Configuration (Declarative Approach)

Conclusion

2. Creating a Namespace Using `kubectl create` Command (Imperative Approach)