Checking Docker Engine Status

To verify if Docker Engine is installed and running correctly on your system, you can use several commands:

Check Docker Version

docker --version

# Expected output:
# Docker version 24.0.6, build ed223bc

Verify Docker is Running

docker ps

# Expected output (when no containers are running):
# CONTAINER ID   IMAGE     COMMAND   CREATED   STATUS    PORTS     NAMES

Test Docker with Hello-World

docker run hello-world

# Expected output:
# Hello from Docker!.....

Installing Docker Engine on Linux

To install Docker Engine on a Linux system, follow these steps:

提示

If you are using a non-Linux system, please refer to the Docker documentation for installation instructions.

Set up Docker's apt repository

# Add Docker's official GPG key:
sudo apt-get update
sudo apt-get install ca-certificates curl
sudo install -m 0755 -d /etc/apt/keyrings
sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
sudo chmod a+r /etc/apt/keyrings/docker.asc

# Add the repository to Apt sources:
echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "${UBUNTU_CODENAME:-$VERSION_CODENAME}") stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
sudo apt-get update

Install the Docker packages

sudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

Installing Docker Compose

Docker Compose V2 is now included as a plugin in most modern Docker installations. If you installed Docker using the steps above, you should already have the docker compose command available:

docker compose version
# Expected output:
# Docker Compose version v2.x.x

If you need to install Docker Compose manually (for example, on older systems or on distributions like Yocto OS), you can download the official binary and place it in your PATH:

mkdir -p ~/.docker/cli-plugins/
curl -SL "https://github.com/docker/compose/releases/latest/download/docker-compose-$(uname -s)-$(uname -m)" -o ~/.docker/cli-plugins/docker-compose
chmod +x ~/.docker/cli-plugins/docker-compose

Note: You may need to adjust the binary path or permissions depending on your environment. Make sure the ~/.docker/cli-plugins/ directory is in your user's PATH or move the binary to a suitable location.

Verify installation

docker compose version
# Expected output:
# Docker Compose version v2.x.x

About uname Command

The uname command is used to print system information, such as the operating system and hardware architecture. In the Docker Compose installation instructions above, uname -s returns the operating system name (e.g., Linux), and uname -m returns the machine hardware name (e.g., x86_64, aarch64).

Common usage and examples:

uname -s   # Print the operating system name
uname -m   # Print the hardware architecture

Example outputs:

$ uname -s
Linux

$ uname -m
x86_64

These values are used to download the correct binary for your platform. For example, on an ARM 64-bit system, uname -m would return aarch64, so the downloaded file would be docker-compose-linux-aarch64.

Basic commands

Docker Commands

Command	Description
docker images	List all Docker images
docker ps	List all running containers
docker ps -a	List all containers (including stopped)
docker start <container_name_or_id>	Start a container
docker stop <container_name_or_id>	Stop a container
docker rm <container_name_or_id>	Remove a container
docker rmi <image_name_or_id>	Remove an image
docker build -t <image_name>:<tag> .	Build an image from a Dockerfile
docker run -d --name <container_name> <image_name>:<tag>	Run a container from an image
docker logs <container_name_or_id>	View logs of a container

Docker Compose basic Commands

Command	Description
docker compose up	Start services defined in docker-compose.yml
docker compose up -d	Start services in detached mode
docker compose down	Stop services
docker compose ps	View running services
docker compose build	Build or rebuild services
docker compose logs	View logs for all services

Replace placeholders (e.g., <container_name_or_id>, <image_name>, <tag>) with your actual values.