Docker Setup & System Information

Commands used to check installation, system status, and configuration.

Check Docker version

docker --version

Example:

docker --version
# Docker version 26.0.0

Display detailed Docker info

docker info

Shows containers, images, storage driver, CPU/memory, etc.

Docker help

docker help

Help for a specific command:

docker run --help

Docker Image Management

Images are templates used to create containers.

List local images

docker images

Example output:

REPOSITORY   TAG       IMAGE ID       SIZE
nginx        latest    605c77e6       142MB

Pull image from registry

docker pull nginx

Specific version:

docker pull python:3.11

Remove image

docker rmi nginx

Remove multiple:

docker rmi image_id1 image_id2

Build image from Dockerfile

docker build -t myapp .

Example:

docker build -t mynodeapp:v1 .

Tag an image

docker tag myapp:v1 username/myapp:v1

Push image to registry

docker push username/myapp:v1

Search images on Docker Hub

docker search redis

Docker Container Management

Containers are running instances of images.

Run container

docker run nginx

Run with interactive terminal:

docker run -it ubuntu bash

Run in detached mode:

docker run -d nginx

Run with port mapping:

docker run -p 8080:80 nginx

Run with name:

docker run --name mynginx nginx

Run with environment variable:

docker run -e MYSQL_ROOT_PASSWORD=secret mysql

List running containers

docker ps

List all containers:

docker ps -a

Stop container

docker stop container_id

Example:

docker stop mynginx

Start container

docker start container_id

Restart container

docker restart container_id

Remove container

docker rm container_id

Remove running container forcefully:

docker rm -f container_id

Container Inspection & Logs

View logs

docker logs container_id

Follow logs:

docker logs -f container_id

Inspect container details

docker inspect container_id

Shows JSON with configuration details.

Show running processes in container

docker top container_id

View container resource usage

docker stats

Example output:

CONTAINER   CPU %   MEM USAGE
nginx       0.12%   20MiB

Executing Commands in Containers

Run command in running container

docker exec container_id ls

Interactive shell:

docker exec -it container_id bash

Example:

docker exec -it mynginx sh

Docker Networking

List networks

docker network ls

Create network

docker network create mynetwork

Inspect network

docker network inspect mynetwork

Connect container to network

docker network connect mynetwork container_id

Remove network

docker network rm mynetwork

Docker Volume Management

Volumes store persistent data.

List volumes

docker volume ls

Create volume

docker volume create myvolume

Inspect volume

docker volume inspect myvolume

Remove volume

docker volume rm myvolume

Mount volume to container

docker run -v myvolume:/data nginx

Bind mount example:

docker run -v $(pwd):/app node

Docker Compose Commands

Used for multi-container applications with Docker Compose.

Start services

docker compose up

Detached mode:

docker compose up -d

Stop services

docker compose down

View running services

docker compose ps

View logs

docker compose logs

Build services

docker compose build

Docker Cleanup Commands

Remove stopped containers

docker container prune

Remove unused images

docker image prune

Remove unused volumes

docker volume prune

Remove everything unused

docker system prune

Aggressive cleanup:

docker system prune -a

Docker File Transfer

Copy files between container and host.

Copy from container:

docker cp container_id:/app/file.txt .

Copy to container:

docker cp file.txt container_id:/app

Advanced Docker Commands

Pause container

docker pause container_id

Unpause container

docker unpause container_id

Rename container

docker rename oldname newname

Update container resources

docker update --memory 500m container_id

Helpful Commands

List container IDs only:

docker ps -q

Remove all containers:

docker rm $(docker ps -aq)

Remove all images:

docker rmi $(docker images -q)