Running kubernetes

Here, we will show how to set up minikube and use kubectl

Installing minikube

You can follow the directions to install minikube here

Using minikube

minikube start --vm-driver=kvm2
minikube status

Creating deployment files

TODO: Go over all the deployment files we need

Installing kubectl

You can follow the directions here to install kubectl

Setting up kubectl

To get kubectl to use the minikube k8s enviroment by creating a new namespace, run this command:

kubectl config set-context --namespace=localdev minikube

Kubectl commands

This command will expose an already running pod named khadga, and attach a LoadBalancer service with a name of khadga-service

kubectl expose deployment khadga --type=LoadBalancer --name=khadga-service

This command uses the kompose file, and will run the get command on everything in the kompose

kubectl get -k .

Will display all the services running in the kubernetes environment (for the default namespace)

kubectl get service
kubectl get deployment
kubectl get pod
kubectl get pod -o wide

Shows how to delete various kubernetes objects like Deployments or Services

kubectl delete deployment khadga
kubectl delete service khadga-service

Uses the kompose file to apply all the config files. Looks for a kompose file

kubectl apply -k .

Creates a new namespace. Namespaces isolate the kubernetes environment

kubectl create namespace localdev 

kubectl config get-contexts

Setting up gcloud

You can follow the directions here to install the gcloud SDK.

Once the gcloud SDK is installed, you will also need to initialize it.

gcloud init

kubectl commands

Allow gcloud to use docker

gcloud auth configure-docker

To set up auth for logging in, run this command.

gcloud auth login

To set the project in google cloud to work with, run this command

gcloud config set project khadga-dev

To show a list of images in GCR run this command, where the argument to repository is the URL for the GCR repo (eg gcr.io, eu.gcr.io, etc), a slash, and then the name of the project

gcloud container images list --repository=gcr.io/khadga-dev

To show the tags of an image use this command

gcloud container images list-tags gcr.io/khadga-dev/khadga

docker-credential-gcloud configure-docker

To get credentials 

gcloud container clusters get-credentials standard-cluster-1 --zone us-central1-a --project khadga-dev

General workflow for testing and deployment

  • docker build your container images
  • tag your images
  • push the images to gcr.io
  • Update the config file for the updated image tag

For testing

  • create a localdev namespace and use it
  • Create the secret so that localdev knows how to use it
  • patch the serviceaccount to use the imagePullSecrets key

For the first step, you need to create a new namespace if you haven't already:

kubectl create namespace localdev

If you have run this step before, you don't need to again. You can go to step 3.

You can either append --namespace=localdev to all kubectl commands, or you can make it your default, where the final argument is the name of your context. To view your contexts:

kubectl config get-contexts

Then to set your namespace to the context you want:

kubectl config set-context --namespace=localdev minikube

Next, you can set up a new secret key by following there directions here

Then you need to patch your serviceaccount to use the key that you downloaded.

kubectl patch serviceaccount default -p '{"imagePullSecrets": [{"name": "gcr-json-key"}]}'