DevOps Problem

1. Set up the Kubernetes Cluster:

Choose a lightweight Kubernetes distribution, such as k3s or MicroK8s, and install it on your target environment.

2. Create Namespace and Deploy Applications:

Create a namespace for your applications and deploy each application individually within the namespace. You can use kubectl apply -f with YAML manifests for each application.

For KeyCloak:

Create a deployment and service for KeyCloak, using PostgreSQL as the database.

# keycloak-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: keycloak
  namespace: your-namespace
spec:
  replicas: 1
  selector:
    matchLabels:
      app: keycloak
  template:
    metadata:
      labels:
        app: keycloak
    spec:
      containers:
        - name: keycloak
          image: jboss/keycloak
          ports:
            - containerPort: 8080
---
# keycloak-service.yaml
apiVersion: v1
kind: Service
metadata:
  name: keycloak
  namespace: your-namespace
spec:
  selector:
    app: keycloak
  ports:
    - protocol: TCP
      port: 8080
      targetPort: 8080

For Ghost:

Create a deployment and service for Ghost, using MySQL as the database.

# ghost-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: ghost
  namespace: your-namespace
spec:
  replicas: 1
  selector:
    matchLabels:
      app: ghost
  template:
    metadata:
      labels:
        app: ghost
    spec:
      containers:
        - name: ghost
          image: ghost
          ports:
            - containerPort: 8080
---
# ghost-service.yaml
apiVersion: v1
kind: Service
metadata:
  name: ghost
  namespace: your-namespace
spec:
  selector:
    app: ghost
  ports:
    - protocol: TCP
      port: 8080
      targetPort: 8080

For PostgreSQL:

Create a deployment and service for PostgreSQL.

# postgres-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: postgres
  namespace: your-namespace
spec:
  replicas: 1
  selector:
    matchLabels:
      app: postgres
  template:
    metadata:
      labels:
        app: postgres
    spec:
      containers:
        - name: postgres
          image: postgres
          ports:
            - containerPort: 5432
---
# postgres-service.yaml
apiVersion: v1
kind: Service
metadata:
  name: postgres
  namespace: your-namespace
spec:
  selector:
    app: postgres
  ports:
    - protocol: TCP
      port: 5432
      targetPort: 5432

For MySQL:

Create a deployment and service for MySQL.

# mysql-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql
  namespace: your-namespace
spec:
  replicas: 1
  selector:
    matchLabels:
      app: mysql
  template:
    metadata:
      labels:
        app: mysql
    spec:
      containers:
        - name: mysql
          image: mysql
          ports:
            - containerPort: 3306
---
# mysql-service.yaml
apiVersion: v1
kind: Service
metadata:
  name: mysql
  namespace: your-namespace
spec:
  selector:
    app: mysql
  ports:
    - protocol: TCP
      port: 3306
      targetPort: 3306

3. Configure Ingress:

Create an Ingress resource to expose your applications through an Ingress controller. If you're using Traefik, make sure it's installed and running link install /

# ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: my-ingress
  namespace: your-namespace
spec:
  rules:
    - host: keycloak.local
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: keycloak
                port:
                  number: 8080
    - host: ghost.local
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: ghost
                port:
                  number: 8080

4. Create setup.sh:

Write a Bash script (setup.sh) to automate the deployment and testing process. This script should apply the YAML files to the Kubernetes cluster.

#!/bin/bash

# Apply Kubernetes manifests
kubectl apply -f keycloak-deployment.yaml
kubectl apply -f keycloak-service.yaml
kubectl apply -f ghost-deployment.yaml
kubectl apply -f ghost-service.yaml
kubectl apply -f postgres-deployment.yaml
kubectl apply -f postgres-service.yaml
kubectl apply -f mysql-deployment.yaml
kubectl apply -f mysql-service.yaml
kubectl apply -f ingress.yaml

# Wait for deployments to be ready
kubectl wait --for=condition=available deployment/keycloak --timeout=300s -n your-namespace
kubectl wait --for=condition=available deployment/ghost --timeout=300s -n your-namespace
kubectl wait --for=condition=available deployment/postgres --timeout=300s -n your-namespace
kubectl wait --for=condition=available deployment/mysql --timeout=300s -n your-namespace

# Perform testing (e.g., wait for services to be available, test authentication and functionality)
# Add your testing logic here

echo "Setup completed successfully!"

5. Write README:

Create a README.md file providing information on the environment, system requirements, instructions for setting up the cluster, and explanations of any security best practices applied.

Security Best Practices:

1. Use Secrets for Sensitive Information: Store database passwords and other sensitive information as Kubernetes secrets.

2. Network Policies: Implement network policies to restrict communication between different applications.

3. Least Privilege Principle: Ensure that applications and services have the minimum necessary permissions to operate.

4. Ingress Controller Security: Configure the Ingress controller securely, and use TLS for encrypted communication.

5. Regular Updates: Keep all components, including Kubernetes itself, up-to-date to patch any security vulnerabilities.

6. Resource Limits: Set resource limits on containers to prevent resource abuse.

Remember to customize the scripts and configurations based on your specific environment and requirements.