prometheus.k8s

The Goal

The purpose of this task is to deploy Prometheus on a Kubernetes cluster and to achieve this task's goal we should master k8s concepts...

So what is Kubernetes in a simple way ?

It's a container orchestration technology that manages clustered environment.

What is a container ?

It's an isolated environment in which you can run your application.. ###Steps before Before jumping to details about k8s let us give a hit about a tool that we need to continue our scenario which is docker

So what is docker ?

It's a tool designed to manage containers by providing the compatibility ..as simple as that

Demo and steps

Before we start with k8s you should install docker because it's required for this demo you can check here : [https://docs.docker.com/install/linux/docker-ce/ubuntu/]

1- Setting up the environment :

Since we are working on a learning environment we need to set up a Kubernetes cluster on our local machine.Actually we will use Minikube to do this. To install Minikube :

first of all you need to install a VM such as VirtualBox <br>
curl -Lo minikube https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64 \
&& chmod +x minikube 
sudo install minikube /usr/local/bin
minikube start

We also need Kubernetes command-line tool which is kubectl that allows you run commands against Kubernetes clusters. -To install it :

curl -LO https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectlcurl -Lo minikube https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64 \
&& chmod +x minikube
chmod +x ./kubectl
sudo mv ./kubectl /usr/local/bin/kubectl
kubectl version

2- Create the deployment yaml file of Prometheus

We should know that Kubernetes uses yaml files as inputs to create it's object that's why we need a yaml deployment file and it's structure should look like this :

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: prometheus
  name: prometheus
spec:
  replicas: 1
  selector:
    matchLabels:
      app: prometheus
  template:
    metadata:
      labels:
        app: prometheus
    spec:
      containers:
      - image: prom/prometheus:v2.11.0
        name: prometheus

After preparing the deployment yaml file you sould tape those commands :

kubectl apply -f prometheus-dep.yaml

See if deployment has bees created :

  kubctl get deployment

You can also see that the pod ans replicaSet has been created too :

    kubctl get pods
    kubectl get replicaset

All good know.

3- Create the Service yaml file

As we mentioned before the service object allows us to access to the container's port via node port and see the pod that is running from web browser for example ..to achieve that we need to configure service yaml file as this one :

 apiVersion: v1
 kind: Service
 metadata:
   name: prometheus-service
 spec:
   type: NodePort
   ports: 
     - targetPort: 9090
       port: 9090
       nodePort: 30008	
   selector:
      app: prometheus	

After preparing the Service yaml file you sould tape this command :

    kubectl apply -f prometheus-service.yaml

you can check by :

 kubectl get services

Now it's time to check from the browser before that you should get the minikube ip adress by taping :

 minikube ip 

go to browser and search : $(minikube ip):30008