Namespaces Walkthrough [page]deterministic

Kubernetes [namespaces](#gloss:namespace) help different projects, teams, or customers to share a Kubernetes cluster.

It does this by providing the following:

1. A scope for [Names](/docs/concepts/overview/working-with-objects/names/). 2. A mechanism to attach authorization and policy to a subsection of the cluster.

Use of multiple namespaces is optional.

This example demonstrates how to use Kubernetes namespaces to subdivide your cluster.

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## Prerequisites

This example assumes the following:

1. You have an [existing Kubernetes cluster](/docs/setup/). 2. You have a basic understanding of Kubernetes [Pods](#gloss:pod), [Services](#gloss:service), and [Deployments](#gloss:deployment).

## Understand the default namespace

By default, a Kubernetes cluster will instantiate a default namespace when provisioning the cluster to hold the default set of Pods, Services, and Deployments used by the cluster.

Assuming you have a fresh cluster, you can inspect the available namespaces by doing the following:

```shell kubectl get namespaces ``` ``` NAME STATUS AGE default Active 13m ```

## Create new namespaces

For this exercise, we will create two additional Kubernetes namespaces to hold our content.

Let's imagine a scenario where an organization is using a shared Kubernetes cluster for development and production use cases.

The development team would like to maintain a space in the cluster where they can get a view on the list of Pods, Services, and Deployments they use to build and run their application. In this space, Kubernetes resources come and go, and the restrictions on who can or cannot modify resources are relaxed to enable agile development.

The operations team would like to maintain a space in the cluster where they can enforce strict procedures on who can or cannot manipulate the set of Pods, Services, and Deployments that run the production site.

One pattern this organization could follow is to partition the Kubernetes cluster into two namespaces: `development` and `production`.

Let's create two new namespaces to hold our work.

Use the file [`namespace-dev.yaml`](/examples/admin/namespace-dev.yaml) which describes a `development` namespace:

Create the `development` namespace using kubectl.

```shell kubectl create -f https://k8s.io/examples/admin/namespace-dev.yaml ```

Save the following contents into file [`namespace-prod.yaml`](/examples/admin/namespace-prod.yaml) which describes a `production` namespace:

And then let's create the `production` namespace using kubectl.

```shell kubectl create -f https://k8s.io/examples/admin/namespace-prod.yaml ```

To be sure things are right, let's list all of the namespaces in our cluster.

```shell kubectl get namespaces --show-labels ``` ``` NAME STATUS AGE LABELS default Active 32m <none> development Active 29s name=development production Active 23s name=production ```

## Create pods in each namespace

A Kubernetes namespace provides the scope for Pods, Services, and Deployments in the cluster.

Users interacting with one namespace do not see the content in another namespace.

To demonstrate this, let's spin up a simple Deployment and Pods in the `development` namespace.

We first check what is the current context:

```shell kubectl config view ``` ```yaml apiVersion: v1 clusters: - cluster: certificate-authority-data: REDACTED server: https://130.211.122.180 name: lithe-cocoa-92103_kubernetes contexts: - context: cluster: lithe-cocoa-92103_kubernetes user: lithe-cocoa-92103_kubernetes name: lithe-cocoa-92103_kubernetes current-context: lithe-cocoa-92103_kubernetes kind: Config preferences: {} users: - name: lithe-cocoa-92103_kubernetes user: client-certificate-data: REDACTED client-key-data: REDACTED token: 65rZW78y8HbwXXtSXuUw9DbP4FLjHi4b - name: lithe-cocoa-92103_kubernetes-basic-auth user: password: h5M0FtUUIflBSdI7 username: admi …(trimmed)