👏🎉 Yay! Yesterday we conquered Namespaces and Services! 💪💻🔗

What are ConfigMaps and Secrets in Kubernetes?

In Kubernetes, ConfigMaps and Secrets are crucial for storing configuration data and sensitive information, respectively. ConfigMaps hold configuration data as key-value pairs, while Secrets store encrypted data.🗝️🔒

In Kubernetes, ConfigMaps and Secrets are like treasure chests 📦 for your application's configuration and sensitive data.

🔧 ConfigMaps hold configuration data as simple key-value pairs, like a neatly organized toolbox 🧰. They help your application access settings and parameters without hassle.

🔒 Secrets, on the other hand, are like locked safes 🗝️, storing sensitive information such as passwords, API tokens, or certificates. They keep this data secure by encrypting it, ensuring only authorized access.

Think of ConfigMaps as the map 🗺️ guiding your application through its settings and Secrets as the hidden treasures 🏴‍☠️ safeguarded from prying eyes. Together, they empower your application to function smoothly while keeping its secrets safe! 🚀

Example: Imagine overseeing a spaceship (Kubernetes cluster) with various components (containers) requiring information to function. ConfigMaps act like a file cabinet, organizing information each component needs in labeled folders (key-value pairs). Meanwhile, Secrets are akin to a safe, safeguarding sensitive data (encrypted data) from unauthorized access. By leveraging ConfigMaps and Secrets, each component receives necessary information while keeping sensitive data secure! 🚀

Read more about ConfigMap & Secret.

Today's tasks: 📋👩‍💻

Task 1: Create a ConfigMap for your Deployment:

• 📝 Create a ConfigMap for your Deployment using a file or command line.

• 🔄 Update the deployment.yml file to include the ConfigMap.

      kind: ConfigMap
      apiVersion: v1
      metadata:
        name: mysql-config
        labels:
          app: todo
      data:
        MYSQL_DB: "todo-db"
  

  

• ✅ Apply the updated deployment using the command: kubectl apply -f deployment.yml -n <namespace-name>.

• 🔍 Verify the ConfigMap's creation by checking the status in your Namespace

  kubectl apply -f configMap.yml

  kubectl get configmap

Task 2: Create a Secret for your Deployment:

• 🗝️ Create a Secret for your Deployment using a file or command line.

• 🔄 Update the deployment.yml file to include the Secret.

  apiVersion: v1
  kind: Secret
  metadata:
    name: mysql-secret
  type: Opaque
  data:
    password: dHJhaW53aXRoc2h1YmhhbQ==

  # To Decode Base64 key
  echo "dHJhaW53aXRoc2h1YmhhbQ==" | base64 --decode

  # To Encode Base64 key
  echo "test@123" | base64

• ✅ Apply the updated deployment using the command: kubectl apply -f deployment.yml -n <namespace-name>.

  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: mysql
    labels:
      app: mysql
  spec:
    replicas: 1
    selector:
      matchLabels:
        app: mysql
    template:
      metadata:
        labels:
          app: mysql
      spec:
        containers:
        - name: mysql
          image: mysql:8
          ports:
          - containerPort: 3306
          env:
          - name: MYSQL_ROOT_PASSWORD
            valueFrom:
              secretKeyRef:
                name: mysql-secret
                key: password
          - name: MYSQL_DATABASE
            valueFrom:
              configMapKeyRef:
                name: mysql-config
                key: MYSQL_DB

  kubectl apply -f deployment.yml

• 🔍 Verify the Secret's creation by checking the status in your Namespace.

  kubectl apply -f secret.yml

  kubectl get secrets

  kubectl get pods

  apiVersion: v1
  kind: Service
  metadata:
    name: mysql-service
  spec:
    ports:
    - name: mysql
      port: 3306
    clusterIP: None
    selector:
      app: mysql

Now apply for the service, so that the pod is exposed.

  kubectl apply -f service.yml

Now on the Worker Node install the MySQL client on it.

  sudo apt install mysql-client-core-8.0

1. Install MySQL: If MySQL is not installed on your system, you'll need to install it. You can do this on Ubuntu using the following command:

    sudo apt update
    sudo apt install mysql-server
   

2. Start MySQL Service: After installing MySQL, the service should start automatically. If not, you can start it manually:

    sudo systemctl start mysql
   

3. Enable MySQL Service: You can also enable MySQL to start on boot:

    sudo systemctl enable mysql
   

4. Check MySQL Service Status: Once MySQL is installed and started, you can verify its status:

    sudo systemctl status mysql
   

5. Verify MySQL Socket: After starting MySQL, ensure that the MySQL socket file is created in the /var/run/mysqld directory. If not, you may need to check the MySQL configuration file (/etc/mysql/mysql.conf.d/mysqld.cnf) and adjust the socket parameter.

6. Connect to MySQL: Once MySQL is running and the socket file is created, you can try connecting to MySQL again using the mysql command:

    mysql -u root -p
   

Keep learning and expanding your knowledge of Kubernetes! 💥🙌 #DevOps #Kubernetes #LearningJourney 🚀🔍