/Introduction-To-Kubernetes

Introduction To Kubernetes

What is Kubernetes

  • an open-source platform designed to automate deploying, scaling, and operating application containers

What the benefits of using K8

Installing kubernetes

  • Click the link Here
  • Once the application has installed, move it from the downloads folder into a new folder that you will name 'kube' in your C drive directory

  • Now we must add this folder to the PATH in our environment variables (system variables)

  • We also want to move the kube folder above our Docker folders, this ensures that Docker does not dictate the installation version of kubernetes

  • We can now run the following command to see if K8 installed successfully

kubectl version --client

Installing Minikube

  • We can install minikube with the link Here

  • After minikube has installed, we can move it from our downloads folder into the same kube folder we made for kubernetes

  • We must enter our Hyper v manager

  • Go to virtual switch manager and create a internal virtual switch, in this instance we will call it minikube

  • We will then have to go to our control panel, and under our Wifi network we must allow connection between this minikube virtual switch

  • We can then start minikube running the below command

minikube start --vm-driver="hyperv" --hyperv-virtual-switch="minikube"
  • When doing this we may receive an error saying Exiting due to GUEST_NOT_FOUND: Failed to start host: Error loading existing host., to overcome this we delete and then start minikube
minikube delete
minikube start

  • This will take a while as it will provision our VM, creating all the virtual resources required
  • It will prepare kubernetes to interact with docker

Running our first Hello World application with K8

  • Below we can see that our master node named minikube is ready to use

kubectl get all  # this will show us all our resources
  • We can now relocate to the into the 03_04 folder which is inside the exercise files folder, once here we can run our hello world yaml file
kubectl create -f helloworld.yaml

Accessing the webpage

  • This will allow us to see our hello world app webpage
kubectl expose deployment helloworld --type=NodePort
  • We can now see below that our application is running on port 31776

  • Using the minikube command below, it will actually take us to the web browser straight away

  • We also have a small recap of the service ans where it has been deployed

# we are reffering to the service ``helloworld`` that we have just created
minikube service helloworld
  • Now as you can see the web browser will be loaded for us

Understanding the hello world application

  • Usually you would have to create the service yml resource and then the deployment yml resource, however using --- in a yml file allows you to create multiple resources in just a single yml file

  • This means we will only have to run this one file to create our resources

kubectl create -f helloworld-all.yml
  • You will see thsat now two resoruces have been created from this one file