Kubernetes is a powerful tool. It can help you manage complex applications and provide you with the ability to easily automate tasks involved in managing them. In this course, we will start exploring Kubernetes from a beginner's standpoint. We will discuss what Kubernetes is and what it does, and we will work with some of the basic functionality of Kubernetes hands-on. We will build a simple Kubernetes cluster. We will also deploy a sample microservice application to the cluster in order to explore how Kubernetes can help easily manage such applications.

A Practical Guide to Kubernetes

## Updating the Jenkins Deployment Definition
Let's take a look at a slightly updated YAML definition.

The **output**, limited to the relevant parts, is as follows.

...
kind: Deployment
...
spec:
  ...
  template:
    ...
    spec:
      containers:
        ...
        volumeMounts:
        - mountPath: /var/jenkins_home
          name: jenkins-home
      volumes:
      - emptyDir: {}
        name: jenkins-home
...


We added a mount that references the `jenkins-home` Volume. The Volume type is, this time, `emptyDir`. We'll discuss the new Volume type soon. But, before we dive into explanations, we'll try to experience its effects.

kubectl apply \
    -f volume/jenkins-empty-dir.yml

kubectl rollout status deploy jenkins

We applied the new definition and waited until the rollout finished.

Now we can open the *New Job* Jenkins screen and repeat the same process we followed before.

open "http://$(minikube ip)/jenkins/newJob"

Please type *test* in the *item name* field, select *Pipeline* as the type, click the *OK* button, and finish by clicking the *Save* button.

Now we'll kill the container and see what happens.

# Updating the Jenkins Deployment Definition
Let's take a look at a slightly updated YAML definition.

In this lesson, we will analyze the state of an updated Jenkins Deployment and discuss emptyDir Volume type.

Persisting State through the emptyDir Volume Type

Updating the Jenkins Deployment Definition