Add network & containerisation

Doc/Containerisation/Docker/Commands.md

@@ -0,0 +1,183 @@
+# Docker – Commands
+
+Practical Docker and Docker Compose command reference. Each block groups related commands with inline comments.
+
+For the concepts behind these commands, see:
+
+- [Docker / Basics](./Basics.md)
+
+---
+
+## 1. Images
+
+```bash
+# List local images
+docker images
+
+# Pull an image from a registry
+docker pull nginx:stable
+
+# Build an image from a Dockerfile in the current directory
+docker build -t myapp:1.0 .
+
+# Build with a custom Dockerfile
+docker build -f Dockerfile.prod -t myapp:prod .
+
+# Tag an existing image
+docker tag myapp:1.0 myapp:latest
+
+# Remove an image
+docker rmi myapp:1.0
+
+# Remove all unused images (dangling and unreferenced)
+docker image prune -a
+```
+
+---
+
+## 2. Container Lifecycle
+
+```bash
+# Run a container in detached mode
+docker run -d --name myapp -p 8080:80 nginx:stable
+
+# Run with a bind mount, environment variable, and restart policy
+docker run -d \
+  --name myapp \
+  -v /host/data:/app/data \
+  -e APP_ENV=production \
+  --restart unless-stopped \
+  myapp:1.0
+
+# Start / stop / restart a container
+docker start myapp
+docker stop myapp
+docker restart myapp
+
+# List running containers
+docker ps
+
+# List all containers (including stopped)
+docker ps -a
+
+# Remove a stopped container
+docker rm myapp
+
+# Stop and remove in one go
+docker stop myapp && docker rm myapp
+```
+
+---
+
+## 3. Logs and Inspection
+
+```bash
+# View container logs
+docker logs myapp
+
+# Follow logs in real time
+docker logs -f myapp
+
+# Show last 50 lines
+docker logs --tail 50 myapp
+
+# Execute a command inside a running container
+docker exec -it myapp bash       # interactive shell
+docker exec myapp ls /app        # one-off command
+
+# Inspect container configuration and networking
+docker inspect myapp
+
+# Show live resource usage for all running containers
+docker stats
+```
+
+---
+
+## 4. Volumes
+
+```bash
+# List volumes
+docker volume ls
+
+# Create a named volume
+docker volume create mydata
+
+# Inspect a volume (shows mount path on host)
+docker volume inspect mydata
+
+# Remove a volume
+docker volume rm mydata
+
+# Remove all unused volumes
+docker volume prune
+```
+
+---
+
+## 5. Networks
+
+```bash
+# List networks
+docker network ls
+
+# Create a user-defined bridge network
+docker network create mynet
+
+# Connect a running container to a network
+docker network connect mynet myapp
+
+# Inspect a network (shows connected containers)
+docker network inspect mynet
+
+# Remove a network
+docker network rm mynet
+```
+
+---
+
+## 6. Docker Compose
+
+```bash
+# Start all services in detached mode
+docker compose up -d
+
+# Stop and remove containers (volumes are kept)
+docker compose down
+
+# Stop and remove containers AND named volumes
+docker compose down -v
+
+# Rebuild images before starting
+docker compose up -d --build
+
+# Restart a single service
+docker compose restart app
+
+# View logs for all services
+docker compose logs -f
+
+# View logs for one service
+docker compose logs -f app
+
+# List containers for the current project
+docker compose ps
+
+# Execute a command inside a service container
+docker compose exec app bash
+```
+
+---
+
+## 7. System Cleanup
+
+```bash
+# Show disk usage by Docker objects (images, containers, volumes, cache)
+docker system df
+
+# Remove all stopped containers, unused networks, dangling images, and build cache
+docker system prune
+
+# Same but also remove unused non-dangling images
+docker system prune -a
+```