Kubernetes Project — Deploy a Flask and MongoDB Microservices

Introduction:-

Kubernetes is a powerful container orchestration tool that enables developers to deploy, manage, and scale containerized applications. While Kubernetes is designed to be easy to use, it's not without its challenges, and troubleshooting is a critical skill that all Kubernetes users must possess. In this blog, we'll explore some common Kubernetes troubleshooting techniques that you can use to diagnose and fix issues with your Kubernetes clusters.

Prerequisites for deployment-

1. Update the system and install docker:

sudo apt update -y
sudo apt install docker.io -y

sudo systemctl start docker
sudo systemctl enable docker

1. Kubeadm installation:

sudo curl -fsSLo /usr/share/keyrings/kubernetes-archive-keyring.gpg https://packages.cloud.google.com/apt/doc/apt-key.gpg

echo "deb [signed-by=/usr/share/keyrings/kubernetes-archive-keyring.gpg] https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.list

sudo apt update -y
sudo apt install kubeadm=1.20.0-00 kubectl=1.20.0-00 kubelet=1.20.0-00 -y

1. To connect with the cluster(for the master node):

sudo su
kubeadm init

  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

kubectl apply -f https://github.com/weaveworks/weave/releases/download/v2.8.1/weave-daemonset-k8s.yaml

kubeadm token create --print-join-command

1. To connect with the cluster(for the Worker node):

sudo su
kubeadm reset pre-flight checks
(*Paste the Join command on worker node and append `--v=5` at end*)
(*kubeadm token create --print-join-command*)

1. To verify cluster connection:-

kubectl get nodes

Let's dive into our deployment------>

Clone the repo:-

1. 1. Create the docker file

     vim Dockerfile
   

   1. 1. Configuration of the docker file

    FROM python:alpine3.7
    COPY . /app
    WORKDIR /app
    RUN pip install -r requirements.txt
    ENV PORT 5000
    EXPOSE 5000
    ENTRYPOINT [ "python" ]
    CMD [ "app.py" ]

1. 3. Now we will make a new deployment file of taskmaster.yml

   

    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: taskmaster
      labels:
        app: taskmaster
    spec:
      replicas: 1
      selector:
        matchLabels:
          app: taskmaster
      template:
        metadata:
          labels:
            app: taskmaster
        spec:
          containers:
            - name: taskmaster
              image: gauriyadav1504/gauri-micro:latest
              ports:
                - containerPort: 5000
              imagePullPolicy: Always
   

   

   

   

   1. 1. Make new taskmaster service file known as taskmaster-svc.yml

    kind: Service
    metadata:
      name: taskmaster-svc
    spec:
      selector:
        app: taskmaster
      ports:
        - port: 80
          targetPort: 5000
          nodePort: 30007
      type: NodePort

1. 1. Make Mongo persistent volume file, that is mongo-pv.yml

    apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: mongo-pv
    spec:
      capacity:
        storage: 256Mi
      accessModes:
        - ReadWriteOnce
      hostPath:
        path: /tmp/db

1. 1. Make a file to claim persistent volume, that is mongo-pv.yml

    apiVersion: v1
    kind: PersistentVolume
    metadata:
      name: mongo-pv
    spec:
      capacity:
        storage: 256Mi
      accessModes:
        - ReadWriteOnce
      hostPath:
        path: /tmp/db

1. 1. Make a mongo file vim mongo.yml

    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: mongo
      labels:
          app: mongo
    spec:
      selector:
        matchLabels:
          app: mongo
      template:
        metadata:
          labels:
            app: mongo
        spec:
          containers:
            - name: mongo
              image: mongo
              ports:
                - containerPort: 27017
              volumeMounts:
                - name: storage
                  mountPath: /data/db
          volumes:
            - name: storage
              persistentVolumeClaim:
                claimName: mongo-pvc

1. 1. make service for mongo file vim mongo-svc.yml

    apiVersion: v1
    kind: Service
    metadata:
      labels:
        app: mongo
      name: mongo
    spec:
      ports:
        - port: 27017
          targetPort: 27017
      selector:
        app: mongo

Thank you for reading!!
\...................................................................................................................................................

~Dushyant Kumar

The above information is up to my understanding. Suggestions are always welcome.

#Kubernetes #DevOps #90daysofdevops #KubeWeek

Shubham Londhe Sir

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