Install Docker Engine on CentOS
To get started with Docker Engine on CentOS, make sure you meet the prerequisites, and then follow the installation steps.
Prerequisites
OS requirements
To install Docker Engine, you need a maintained version of one of the following CentOS versions:
- CentOS 9 (stream)
The centos-extras
repository must be enabled. This repository is enabled by
default. If you have disabled it, you need to re-enable it.
Uninstall old versions
Older versions of Docker went by docker
or docker-engine
.
Uninstall any such older versions before attempting to install a new version,
along with associated dependencies.
$ sudo yum remove docker \
docker-client \
docker-client-latest \
docker-common \
docker-latest \
docker-latest-logrotate \
docker-logrotate \
docker-engine
yum
might report that you have none of these packages installed.
Images, containers, volumes, and networks stored in /var/lib/docker/
aren't
automatically removed when you uninstall Docker.
Installation methods
You can install Docker Engine in different ways, depending on your needs:
You can set up Docker's repositories and install from them, for ease of installation and upgrade tasks. This is the recommended approach.
You can download the RPM package, install it manually, and manage upgrades completely manually. This is useful in situations such as installing Docker on air-gapped systems with no access to the internet.
In testing and development environments, you can use automated convenience scripts to install Docker.
Install using the rpm repository
Before you install Docker Engine for the first time on a new host machine, you need to set up the Docker repository. Afterward, you can install and update Docker from the repository.
Set up the repository
Install the yum-utils
package (which provides the yum-config-manager
utility) and set up the repository.
$ sudo yum install -y yum-utils
$ sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
Install Docker Engine
Install Docker Engine, containerd, and Docker Compose:
To install the latest version, run:
$ sudo yum install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin
If prompted to accept the GPG key, verify that the fingerprint matches
060A 61C5 1B55 8A7F 742B 77AA C52F EB6B 621E 9F35
, and if so, accept it.This command installs Docker, but it doesn't start Docker. It also creates a
docker
group, however, it doesn't add any users to the group by default.To install a specific version, start by listing the available versions in the repository:
$ yum list docker-ce --showduplicates | sort -r docker-ce.x86_64 3:27.1.1-1.el9 docker-ce-stable docker-ce.x86_64 3:27.1.0-1.el9 docker-ce-stable <...>
The list returned depends on which repositories are enabled, and is specific to your version of CentOS (indicated by the
.el9
suffix in this example).Install a specific version by its fully qualified package name, which is the package name (
docker-ce
) plus the version string (2nd column), separated by a hyphen (-
). For example,docker-ce-3:27.1.1-1.el9
.Replace
<VERSION_STRING>
with the desired version and then run the following command to install:$ sudo yum install docker-ce-<VERSION_STRING> docker-ce-cli-<VERSION_STRING> containerd.io docker-buildx-plugin docker-compose-plugin
This command installs Docker, but it doesn't start Docker. It also creates a
docker
group, however, it doesn't add any users to the group by default.Start Docker.
$ sudo systemctl start docker
Verify that the Docker Engine installation is successful by running the
hello-world
image.$ sudo docker run hello-world
This command downloads a test image and runs it in a container. When the container runs, it prints a confirmation message and exits.
You have now successfully installed and started Docker Engine.
Tip
Receiving errors when trying to run without root?
The
docker
user group exists but contains no users, which is why you’re required to usesudo
to run Docker commands. Continue to Linux postinstall to allow non-privileged users to run Docker commands and for other optional configuration steps.
Upgrade Docker Engine
To upgrade Docker Engine, follow the installation instructions, choosing the new version you want to install.
Install from a package
If you can't use Docker's rpm
repository to install Docker Engine, you can
download the .rpm
file for your release and install it manually. You need to
download a new file each time you want to upgrade Docker Engine.
Go to https://download.docker.com/linux/centos/ and choose your version of CentOS. Then browse to
x86_64/stable/Packages/
and download the.rpm
file for the Docker version you want to install.Install Docker Engine, changing the following path to the path where you downloaded the Docker package.
$ sudo yum install /path/to/package.rpm
Docker is installed but not started. The
docker
group is created, but no users are added to the group.Start Docker.
$ sudo systemctl start docker
Verify that the Docker Engine installation is successful by running the
hello-world
image.$ sudo docker run hello-world
This command downloads a test image and runs it in a container. When the container runs, it prints a confirmation message and exits.
You have now successfully installed and started Docker Engine.
Tip
Receiving errors when trying to run without root?
The
docker
user group exists but contains no users, which is why you’re required to usesudo
to run Docker commands. Continue to Linux postinstall to allow non-privileged users to run Docker commands and for other optional configuration steps.
Upgrade Docker Engine
To upgrade Docker Engine, download the newer package files and repeat the
installation procedure, using yum -y upgrade
instead of yum -y install
, and point to the new files.
Install using the convenience script
Docker provides a convenience script at
https://get.docker.com/ to install Docker into
development environments non-interactively. The convenience script isn't
recommended for production environments, but it's useful for creating a
provisioning script tailored to your needs. Also refer to the
install using the repository steps to learn
about installation steps to install using the package repository. The source code
for the script is open source, and you can find it in the
docker-install
repository on GitHub.
Always examine scripts downloaded from the internet before running them locally. Before installing, make yourself familiar with potential risks and limitations of the convenience script:
- The script requires
root
orsudo
privileges to run. - The script attempts to detect your Linux distribution and version and configure your package management system for you.
- The script doesn't allow you to customize most installation parameters.
- The script installs dependencies and recommendations without asking for confirmation. This may install a large number of packages, depending on the current configuration of your host machine.
- By default, the script installs the latest stable release of Docker, containerd, and runc. When using this script to provision a machine, this may result in unexpected major version upgrades of Docker. Always test upgrades in a test environment before deploying to your production systems.
- The script isn't designed to upgrade an existing Docker installation. When using the script to update an existing installation, dependencies may not be updated to the expected version, resulting in outdated versions.
Tip: preview script steps before running
You can run the script with the
--dry-run
option to learn what steps the script will run when invoked:$ curl -fsSL https://get.docker.com -o get-docker.sh $ sudo sh ./get-docker.sh --dry-run
This example downloads the script from https://get.docker.com/ and runs it to install the latest stable release of Docker on Linux:
$ curl -fsSL https://get.docker.com -o get-docker.sh
$ sudo sh get-docker.sh
Executing docker install script, commit: 7cae5f8b0decc17d6571f9f52eb840fbc13b2737
<...>
You have now successfully installed and started Docker Engine. The docker
service starts automatically on Debian based distributions. On RPM
based
distributions, such as CentOS, Fedora, RHEL or SLES, you need to start it
manually using the appropriate systemctl
or service
command. As the message
indicates, non-root users can't run Docker commands by default.
Use Docker as a non-privileged user, or install in rootless mode?
The installation script requires
root
orsudo
privileges to install and use Docker. If you want to grant non-root users access to Docker, refer to the post-installation steps for Linux. You can also install Docker withoutroot
privileges, or configured to run in rootless mode. For instructions on running Docker in rootless mode, refer to run the Docker daemon as a non-root user (rootless mode).
Install pre-releases
Docker also provides a convenience script at
https://test.docker.com/ to install pre-releases of
Docker on Linux. This script is equal to the script at get.docker.com
, but
configures your package manager to use the test channel of the Docker package
repository. The test channel includes both stable and pre-releases (beta
versions, release-candidates) of Docker. Use this script to get early access to
new releases, and to evaluate them in a testing environment before they're
released as stable.
To install the latest version of Docker on Linux from the test channel, run:
$ curl -fsSL https://test.docker.com -o test-docker.sh
$ sudo sh test-docker.sh
Upgrade Docker after using the convenience script
If you installed Docker using the convenience script, you should upgrade Docker using your package manager directly. There's no advantage to re-running the convenience script. Re-running it can cause issues if it attempts to re-install repositories which already exist on the host machine.
Uninstall Docker Engine
Uninstall the Docker Engine, CLI, containerd, and Docker Compose packages:
$ sudo yum remove docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin docker-ce-rootless-extras
Images, containers, volumes, or custom configuration files on your host aren't automatically removed. To delete all images, containers, and volumes:
$ sudo rm -rf /var/lib/docker $ sudo rm -rf /var/lib/containerd
You have to delete any edited configuration files manually.
Next steps
- Continue to Post-installation steps for Linux.