Cheatsheet Phase 3 - Cloud & Containers

Docker - Images

docker pull image:tag
docker images / docker image ls
docker build -t name:tag .
docker build -f Dockerfile.prod -t app .
docker tag img:v1 registry/img:v1
docker push registry/img:v1
docker rmi image:tag
docker image prune -a

Docker - Conteneurs

docker run -d --name web nginx
docker run -d -p 8080:80 nginx
docker run -d -v /host:/container nginx
docker run --rm -it ubuntu bash
docker ps / docker ps -a
docker stop/start/restart name
docker rm name / docker rm -f name
docker logs -f name
docker exec -it name bash
docker inspect name
docker stats

Docker - Reseau & Volumes

# Reseaux
docker network ls
docker network create mynet
docker network connect mynet container

# Volumes
docker volume ls
docker volume create myvol
docker run -v myvol:/data nginx

# Nettoyage
docker system prune -a
docker volume prune

Dockerfile

FROM node:18-alpine
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production
COPY . .
ENV NODE_ENV=production
EXPOSE 3000
USER node
CMD ["node", "server.js"]

# Multi-stage
FROM node:18 AS builder
RUN npm run build

FROM node:18-alpine
COPY --from=builder /app/dist ./

Docker Compose

version: '3.8'
services:
  web:
    build: .
    ports: ["3000:3000"]
    environment:
      - NODE_ENV=production
    depends_on:
      db:
        condition: service_healthy
    networks: [app-net]
  db:
    image: postgres:15
    volumes: [pgdata:/var/lib/postgresql/data]
    healthcheck:
      test: ["CMD", "pg_isready"]
volumes:
  pgdata:
networks:
  app-net:

docker compose up -d
docker compose down -v
docker compose logs -f
docker compose exec web bash

Kubernetes - kubectl Basics

# Contexte
kubectl config get-contexts
kubectl config use-context ctx

# Info
kubectl get nodes
kubectl get pods [-n namespace]
kubectl get svc,deploy,rs
kubectl describe pod name
kubectl logs pod [-f]
kubectl exec -it pod -- bash

# Apply
kubectl apply -f file.yaml
kubectl delete -f file.yaml
kubectl delete pod name

K8s - Pod & Deployment

# deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: web
spec:
  replicas: 3
  selector:
    matchLabels:
      app: web
  template:
    metadata:
      labels:
        app: web
    spec:
      containers:
      - name: web
        image: nginx:1.25
        ports:
        - containerPort: 80
        resources:
          requests:
            memory: "128Mi"
            cpu: "100m"
          limits:
            memory: "256Mi"
            cpu: "500m"

K8s - Service & Ingress

# service.yaml
apiVersion: v1
kind: Service
metadata:
  name: web-svc
spec:
  selector:
    app: web
  ports:
  - port: 80
    targetPort: 80
  type: ClusterIP  # NodePort, LoadBalancer

# ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: web-ingress
spec:
  rules:
  - host: app.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: web-svc
            port:
              number: 80

K8s - ConfigMap & Secret

# ConfigMap
kubectl create configmap cfg \
  --from-literal=KEY=value
kubectl create configmap cfg \
  --from-file=config.properties

# Secret
kubectl create secret generic sec \
  --from-literal=password=xxx

# Usage dans Pod
envFrom:
- configMapRef:
    name: cfg
- secretRef:
    name: sec

# Ou variable unique
env:
- name: DB_PASS
  valueFrom:
    secretKeyRef:
      name: sec
      key: password

K8s - Scaling & Updates

# Scale manuel
kubectl scale deploy web --replicas=5

# Autoscaling
kubectl autoscale deploy web \
  --min=2 --max=10 --cpu-percent=80

# Rolling update
kubectl set image deploy/web \
  web=nginx:1.26

# Rollback
kubectl rollout undo deploy/web
kubectl rollout status deploy/web
kubectl rollout history deploy/web

Helm

# Repos
helm repo add bitnami \
  https://charts.bitnami.com/bitnami
helm repo update
helm search repo nginx

# Install
helm install myrelease bitnami/nginx
helm install myrelease ./mychart \
  -f values.yaml
helm upgrade myrelease ./mychart
helm uninstall myrelease

# Debug
helm list
helm status myrelease
helm template ./mychart

AWS CLI - EC2

# Configuration
aws configure
aws sts get-caller-identity

# EC2
aws ec2 describe-instances
aws ec2 run-instances \
  --image-id ami-xxx \
  --instance-type t3.micro \
  --key-name mykey
aws ec2 start-instances --instance-ids i-xxx
aws ec2 stop-instances --instance-ids i-xxx
aws ec2 terminate-instances --instance-ids i-xxx

# Security Groups
aws ec2 describe-security-groups
aws ec2 authorize-security-group-ingress \
  --group-id sg-xxx \
  --protocol tcp --port 22 \
  --cidr 0.0.0.0/0

AWS CLI - S3

# Buckets
aws s3 ls
aws s3 mb s3://mybucket
aws s3 rb s3://mybucket --force

# Objects
aws s3 ls s3://bucket/prefix/
aws s3 cp file.txt s3://bucket/
aws s3 cp s3://bucket/file.txt ./
aws s3 sync ./folder s3://bucket/folder
aws s3 rm s3://bucket/file.txt
aws s3 rm s3://bucket/ --recursive

# Presigned URL
aws s3 presign s3://bucket/file \
  --expires-in 3600

AWS - Services Cles

Azure CLI

# Login
az login
az account list
az account set -s "subscription"

# Resource Groups
az group list
az group create -n mygroup -l westeurope

# VMs
az vm list
az vm create -g mygroup -n myvm \
  --image UbuntuLTS --size Standard_B1s
az vm start/stop/delete -g mygroup -n myvm

# Storage
az storage account list
az storage blob upload -c container \
  -f file.txt -n file.txt

Terraform - Basics

# Commandes
terraform init      # Initialize
terraform plan      # Preview
terraform apply     # Create
terraform destroy   # Delete
terraform fmt       # Format
terraform validate  # Check syntax

# State
terraform state list
terraform state show resource
terraform import aws_instance.web i-xxx

# Workspaces
terraform workspace list
terraform workspace new dev
terraform workspace select dev

Terraform - HCL Syntax

# Provider
provider "aws" {
  region = "eu-west-1"
}

# Resource
resource "aws_instance" "web" {
  ami           = var.ami_id
  instance_type = "t3.micro"
  tags = {
    Name = "web-${var.env}"
  }
}

# Variable
variable "env" {
  type    = string
  default = "dev"
}

# Output
output "ip" {
  value = aws_instance.web.public_ip
}

# Data source
data "aws_ami" "ubuntu" {
  most_recent = true
  owners      = ["099720109477"]
}

Terraform - Modules & Backend

# Module usage
module "vpc" {
  source  = "./modules/vpc"
  cidr    = "10.0.0.0/16"
  env     = var.env
}

output "vpc_id" {
  value = module.vpc.vpc_id
}

# Remote backend (S3)
terraform {
  backend "s3" {
    bucket = "tf-state-bucket"
    key    = "prod/terraform.tfstate"
    region = "eu-west-1"
    dynamodb_table = "tf-locks"
  }
}

Ansible - Basics

# Inventory (hosts.ini)
[webservers]
web1 ansible_host=10.0.1.10
web2 ansible_host=10.0.1.11

[dbservers]
db1 ansible_host=10.0.2.10

[all:vars]
ansible_user=ubuntu
ansible_ssh_private_key_file=~/.ssh/key.pem

# Ad-hoc commands
ansible all -m ping
ansible web -m shell -a "uptime"
ansible db -m apt -a "name=mysql state=present" -b

Ansible - Playbook

# playbook.yml
---
- name: Configure web servers
  hosts: webservers
  become: yes
  vars:
    http_port: 80
  tasks:
    - name: Install nginx
      apt:
        name: nginx
        state: present
        update_cache: yes

    - name: Start nginx
      service:
        name: nginx
        state: started
        enabled: yes

    - name: Copy config
      template:
        src: nginx.conf.j2
        dest: /etc/nginx/nginx.conf
      notify: Restart nginx

  handlers:
    - name: Restart nginx
      service:
        name: nginx
        state: restarted

ansible-playbook -i hosts.ini playbook.yml

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