Docker Commands

Docker provides a comprehensive set of commands that enable you to manage containers, images, networks, and other Docker objects effectively. Mastering these commands is essential for optimizing your Docker workflows, whether you're building images, running containers, or configuring networks.

Basic Docker Commands

These fundamental Docker commands are crucial for working with containers and images:

docker run

Purpose: Creates and starts a new container from a Docker image.
Example:
```
docker run -d -p 80:80 nginx
```
Runs an Nginx container in detached mode (-d), mapping port 80 of the container to port 80 on the host (-p).

docker ps

Purpose: Lists all running containers.
Example:
```
docker ps
```
Use -a to view all containers, including stopped ones:
```
docker ps -a
```

docker stop

Purpose: Stops a running container.
Example:
```
docker stop container_id
```
Replace container_id with the container's ID or name.

docker rm

Purpose: Removes a stopped container.

Example:

docker rm container_id

To remove all stopped containers:

docker rm $(docker ps -a -q)

docker rmi

Purpose: Removes one or more Docker images from your local system.
Example:
```
docker rmi image_id
```
To remove unused (dangling) images:
```
docker image prune
```

docker images

Purpose: Lists all Docker images on your local machine.
Example:
```
docker images
```

docker build

Purpose: Creates a Docker image from a Dockerfile.
Example:
```
docker build -t myapp .
```
Builds an image named myapp from the Dockerfile in the current directory.

docker pull

Purpose: Downloads a Docker image from a registry.
Example:
```
docker pull redis
```
Pulls the Redis image from Docker Hub.

docker push

Purpose: Uploads a Docker image to a registry.
Example:
```
docker push myrepo/myapp
```
Pushes the myapp image to the myrepo repository on Docker Hub or another registry.

docker exec

Purpose: Runs a command inside a running container.
Example:
```
docker exec -it container_id bash
```
Opens an interactive shell (bash) inside the specified container.

docker logs

Purpose: Fetches the logs of a running container.

Example:

docker logs container_id

Use -f to follow the log output in real-time:

docker logs -f container_id

Docker Networking Commands

Manage and configure Docker networks with these commands:

docker network ls

Purpose: Lists all Docker networks.
Example:
```
docker network ls
```

docker network create

Purpose: Creates a new Docker network.
Example:
```
docker network create mynetwork
```

docker network connect

Purpose: Connects a container to a network.

Example:

docker network connect mynetwork container_id

docker network inspect

Purpose: Displays detailed information about a network.
Example:
```
docker network inspect mynetwork
```

docker network rm

Purpose: Removes one or more Docker networks.
Example:
```
docker network rm mynetwork
```

Learn more about container networking.

Docker Volume Commands

Docker volumes persist data generated by and used by containers. These commands help you manage Docker volumes:

docker volume ls

Purpose: Lists all Docker volumes.
Example:
```
docker volume ls
```

docker volume create

Purpose: Creates a new volume.
Example:
```
docker volume create myvolume
```

docker volume inspect

Purpose: Displays detailed information about a volume.
Example:
```
docker volume inspect myvolume
```

docker volume rm

Purpose: Removes a Docker volume.
Example:
```
docker volume rm myvolume
```

docker volume prune

Purpose: Removes all unused volumes.
Example:
```
docker volume prune
```

Dive deeper into Docker volumes.

Advanced Docker Commands

These commands are useful for more advanced Docker operations:

docker-compose

Purpose: Interacts with Docker Compose files to define and run multi-container applications.
Example:
```
docker-compose up
```
Starts all the services defined in a docker-compose.yml file.

docker inspect

Purpose: Returns detailed information about a Docker object, such as a container or image.
Example:
```
docker inspect container_id
```

docker stats

Purpose: Displays real-time resource usage statistics for containers.
Example:
```
docker stats
```

docker system prune

Purpose: Removes all unused containers, networks, images, and optionally, volumes.
Example:
```
docker system prune
```
Use -a to remove all unused images, not just dangling ones:
```
docker system prune -a
```

docker tag

Purpose: Creates a new tag for an existing Docker image.
Example:
```
docker tag myimage:latest myrepo/myimage:v1.0
```
Tags the image myimage:latest with a new name and version, myrepo/myimage:v1.0.

docker cp

Purpose: Copies files/folders between a container and the local filesystem.
Example:
```
docker cp container_id:/path/to/file /local/path
```
Copies a file from the container to the local machine.