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Use Docker’s official packages rather than the older distribution builds. Ubuntu and Debian install Docker Engine from Docker’s APT repository; CentOS uses Docker’s RPM repository; Windows 10 and 11 normally use Docker Desktop with a WSL 2 or Hyper-V backend. Remove conflicting packages first, then verify every installation with docker run hello-world. Linux users should also check the systemd service.
Before you install Docker
Choose the instructions for the operating system and edition you actually run. You need an administrator account (or sudo) for package installation. Docker’s current Ubuntu Engine instructions support 64-bit Ubuntu Resolute 26.04 LTS, Noble 24.04 LTS, and Jammy 22.04 LTS on amd64, armhf, arm64, s390x, and ppc64le. Debian and CentOS support depends on the release and architecture supported by Docker’s repository.
Docker recommends distribution packages or Docker Desktop for normal use. Static binaries require manual updates and are mainly intended for testing. Convenience scripts exist in the Linux documentation, but Docker recommends them only for testing and development.
Remove packages that conflict with Docker’s packages
On Ubuntu and Debian, remove older or alternative packages before adding Docker’s repository:
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sudo apt remove docker.io docker-compose docker-compose-v2 docker-doc podman-docker containerd runcIf a package is not installed, APT reports that and continues. On CentOS, remove any previously installed Docker or container runtime packages before proceeding:
sudo dnf remove docker docker-client docker-client-latest docker-common docker-latest docker-latest-logrotate docker-logrotate docker-engine podman runcRemoving packages does not automatically delete images, containers, volumes, or files under Docker’s data directory, but always back up important data before changing an existing installation.
Install Docker Engine on Ubuntu
The following uses Docker’s official APT repository and installs Engine, the CLI, containerd, Buildx, and the Compose plugin.
- Install repository prerequisites.
sudo apt update sudo apt install ca-certificates curl - Install and authorize Docker’s signing key.
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 - Create the deb822 repository definition.
sudo tee /etc/apt/sources.list.d/docker.sources <<EOF Types: deb URIs: https://download.docker.com/linux/ubuntu Suites: $(. /etc/os-release && echo "${UBUNTU_CODENAME:-$VERSION_CODENAME}") Components: stable Architectures: $(dpkg --print-architecture) Signed-By: /etc/apt/keyrings/docker.asc EOF - Install Docker.
sudo apt update sudo apt install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin - Check the daemon and run Docker’s test container.
sudo systemctl status docker sudo docker run hello-world
The hello-world command downloads a test image, runs it in a container, prints a confirmation message, and exits. A successful run proves that the CLI can contact the daemon and that the daemon can pull and start an image.
Install Docker Engine on Debian
Debian uses the same package set as Ubuntu, but the repository path and distribution codename are different.
- Remove conflicting packages and install prerequisites.
sudo apt remove docker.io docker-compose docker-compose-v2 docker-doc podman-docker containerd runc sudo apt update sudo apt install ca-certificates curl - Add Docker’s signing key.
sudo install -m 0755 -d /etc/apt/keyrings sudo curl -fsSL https://download.docker.com/linux/debian/gpg -o /etc/apt/keyrings/docker.asc sudo chmod a+r /etc/apt/keyrings/docker.asc - Add the official Debian repository.
sudo tee /etc/apt/sources.list.d/docker.sources <<EOF Types: deb URIs: https://download.docker.com/linux/debian Suites: $(. /etc/os-release && echo "$VERSION_CODENAME") Components: stable Architectures: $(dpkg --print-architecture) Signed-By: /etc/apt/keyrings/docker.asc EOF - Install Engine and related tools.
sudo apt update sudo apt install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin - Verify the service and image execution.
sudo systemctl status docker sudo docker run hello-world
On Debian testing, or on derivatives such as Kali, the detected codename may not have a matching Docker repository. If APT reports that the release has no installation candidate, replace the detected codename in /etc/apt/sources.list.d/docker.sources with the corresponding Debian codename—for example, trixie—only when that mapping matches your system and Docker’s supported repository.
Install Docker Engine on CentOS
CentOS uses Docker’s RPM repository. Installing the packages does not start the daemon automatically, so enable and start it explicitly.
- Remove conflicting packages.
sudo dnf remove docker docker-client docker-client-latest docker-common docker-latest docker-latest-logrotate docker-logrotate docker-engine podman runc - Install the repository-management plugin.
sudo dnf -y install dnf-plugins-core - Add Docker’s official repository.
sudo dnf config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo - Install Engine, containerd, Buildx, and Compose.
sudo dnf install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin - Enable Docker at boot and start it now.
sudo systemctl enable --now docker - Run the verification container.
sudo docker run hello-world
The installation creates a docker group but does not add your users to it. Until you deliberately configure access, use sudo with Docker commands.
Install Docker Desktop on Windows 10 or 11
Windows normally runs Linux containers through Docker Desktop. Docker’s current requirements list 64-bit Windows 10 Enterprise, Pro, or Education 22H2 (build 19045), and 64-bit Windows 11 Enterprise, Pro, or Education 23H2 (build 22631) or higher, within Microsoft’s servicing timeline.
Edition and hardware limits
- WSL 2 requires a 64-bit processor with SLAT support, at least 8 GB of RAM, hardware virtualization enabled in firmware, and the WSL 2 feature.
- Windows containers require Pro or Enterprise. Home and Education editions support Linux containers only.
- In firmware, Intel VT-x or AMD-V may be labeled “virtualization technology,” “SVM,” or a similar setting. Enable it before installing if Docker reports that virtualization is unavailable.
Interactive installation
- Download
Docker Desktop Installer.exefrom Docker’s official Windows distribution. - Run the installer and choose either per-user or all-users installation.
- On the configuration page, select the WSL 2 or Hyper-V backend available on your machine. WSL 2 is the usual choice for Linux containers.
- Complete the wizard and start Docker Desktop from the Start menu.
- Open PowerShell and verify the installation:
docker version
docker run hello-worldInstall from PowerShell
Per-user installation does not require administrator privileges and installs under %LOCALAPPDATA%ProgramsDockerDesktop:
Start-Process 'Docker Desktop Installer.exe' -Wait -ArgumentList 'install', '--user'For an all-users installation, open an elevated PowerShell window:
Start-Process 'Docker Desktop Installer.exe' -Wait installAfter either command finishes, launch Docker Desktop and wait for its status to show that the engine is running before executing docker version.
Allow Docker commands without sudo on Linux
Docker’s daemon normally requires sudo. You can add your account to the docker group:
sudo groupadd docker
sudo usermod -aG docker $USERLog out and back in completely, or refresh the group membership in the current shell:
newgrp docker
docker run hello-worldThis is a security decision, not just a convenience setting: Docker explicitly warns that membership in the docker group grants root-level privileges. On Debian and Ubuntu, Docker starts at boot by default. On other systemd distributions, enable both services when required:
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sudo systemctl enable docker.service
sudo systemctl enable containerd.serviceDocker Desktop for Linux: when it makes sense
Docker Desktop is also available for Linux as .deb or .rpm packages for Ubuntu, Debian, RHEL, and Fedora on x86_64/amd64. It is optional; the native Engine installation above is generally simpler on a Linux server.
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If Engine and Docker Desktop coexist, Docker uses contexts to select the daemon. The native daemon is commonly the default context and Desktop uses desktop-linux:
docker context ls
docker context use default
docker context use desktop-linuxCheck the active context before troubleshooting a “missing” image or container: each daemon has its own images, containers, networks, and volumes.
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docker: command not found or an unrecognized command
The CLI package is missing, the installation did not finish, or your shell’s PATH has not refreshed. Re-run the package installation, open a new terminal, and check docker version.
Cannot connect to the Docker daemon
On Linux, inspect and start the service:
sudo systemctl status docker
sudo systemctl start dockerOn Windows, start Docker Desktop and wait until it reports a running engine. If Desktop cannot start, check that virtualization and the selected WSL 2 or Hyper-V feature are enabled.
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APT reports an unsupported release or no installation candidate
Inspect /etc/os-release and the codename in /etc/apt/sources.list.d/docker.sources. Debian derivatives may need the matching Debian codename rather than the derivative’s name. Do not substitute a random release: an incorrect repository can install incompatible packages.
Permission denied after adding the docker group
The group change applies only to new login sessions. Log out and back in, or run newgrp docker. If the command then works, remember that the group has root-equivalent access.
hello-world cannot download its image
The daemon is running, but it cannot reach the registry. Check DNS, proxy, firewall, and corporate TLS inspection settings. A successful local service status alone does not prove external registry connectivity.
Docker Desktop says virtualization is disabled
Enable hardware virtualization in UEFI/BIOS, confirm that the CPU supports SLAT, and ensure the WSL 2 or Hyper-V Windows feature selected during setup is installed. Reboot Windows after changing firmware or optional-feature settings.
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