Kubernetes - Namespace

Namespace provides an additional qualification to a resource name. This is helpful when multiple teams are using the same cluster and there is a potential of name collision. It can be as a virtual wall between multiple clusters.

Functionality of Namespace

Following are some of the important functionalities of a Namespace in Kubernetes −

  • Namespaces help pod-to-pod communication using the same namespace.

  • Namespaces are virtual clusters that can sit on top of the same physical cluster.

  • They provide logical separation between the teams and their environments.

Create a Namespace

The following command is used to create a namespace.

apiVersion: v1
kind: Namespce
metadata
   name: elk

Control the Namespace

The following command is used to control the namespace.

$ kubectl create –f namespace.yml ---------> 1
$ kubectl get namespace -----------------> 2
$ kubectl get namespace <Namespace name> ------->3
$ kubectl describe namespace <Namespace name> ---->4
$ kubectl delete namespace <Namespace name>

In the above code,

  • We are using the command to create a namespace.
  • This will list all the available namespace.
  • This will get a particular namespace whose name is specified in the command.
  • This will describe the complete details about the service.
  • This will delete a particular namespace present in the cluster.

Using Namespace in Service - Example

Following is an example of a sample file for using namespace in service.

apiVersion: v1
kind: Service
metadata:
   name: elasticsearch
   namespace: elk
   labels:
      component: elasticsearch
spec:
   type: LoadBalancer
   selector:
      component: elasticsearch
   ports:
   - name: http
      port: 9200
      protocol: TCP
   - name: transport
      port: 9300
      protocol: TCP

In the above code, we are using the same namespace under service metadata with the name of elk.

Advertisements