docs/engine/installation/linux/docker-ce/centos.md

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---
description: Instructions for installing Docker CE on CentOS
keywords: requirements, apt, installation, centos, rpm, install, uninstall, upgrade, update
redirect_from:
- /engine/installation/centos/
title: Get Docker CE for CentOS
---
To get started with Docker CE on CentOS, make sure you
[meet the prerequisites](#prerequisites), then
[install Docker](#install-docker-ce).
## Prerequisites
### Docker EE customers
To install Docker Enterprise Edition (Docker EE), go to
[Get Docker EE for CentOS](/engine/installation/linux/docker-ee/centos/)
**instead of this topic**.
To learn more about Docker EE, see
[Docker Enterprise Edition](https://www.docker.com/enterprise-edition/){: target="_blank" class="_" }.
### OS requirements
To install Docker CE, you need a maintained version of CentOS 7. Archived
versions aren't supported or tested.
The `centos-extras` repository must be enabled. This repository is enabled by
default, but if you have disabled it, you need to
[re-enable it](https://wiki.centos.org/AdditionalResources/Repositories){: target="_blank" class="_" }.
### Uninstall old versions
Older versions of Docker were called `docker` or `docker-engine`. If these are
installed, uninstall them, along with associated dependencies.
```bash
$ sudo yum remove docker \
docker-common \
docker-selinux \
docker-engine
```
It's OK if `yum` reports that none of these packages are installed.
The contents of `/var/lib/docker/`, including images, containers, volumes, and
networks, are preserved. The Docker CE package is now called `docker-ce`.
## Install Docker CE
You can install Docker CE in different ways, depending on your needs:
- Most users
[set up Docker's repositories](#install-using-the-repository) and install
from them, for ease of installation and upgrade tasks. This is the
recommended approach.
- Some users download the RPM package and
[install it manually](#install-from-a-package) 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, some users choose to use automated
[convenience scripts](#install-using-the-convenience-script) to install Docker.
### Install using the repository
Before you install Docker CE 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
{% assign download-url-base = "https://download.docker.com/linux/centos" %}
1. Install required packages. `yum-utils` provides the `yum-config-manager`
utility, and `device-mapper-persistent-data` and `lvm2` are required by the
`devicemapper` storage driver.
```bash
$ sudo yum install -y yum-utils \
device-mapper-persistent-data \
lvm2
```
2. Use the following command to set up the **stable** repository. You always
need the **stable** repository, even if you want to install builds from the
**edge** or **test** repositories as well.
```bash
$ sudo yum-config-manager \
--add-repo \
{{ download-url-base }}/docker-ce.repo
```
3. **Optional**: Enable the **edge** and **test** repositories. These
repositories are included in the `docker.repo` file above but are disabled
by default. You can enable them alongside the stable repository.
```bash
$ sudo yum-config-manager --enable docker-ce-edge
```
```bash
$ sudo yum-config-manager --enable docker-ce-test
```
You can disable the **edge** or **test** repository by running the
`yum-config-manager` command with the `--disable` flag. To re-enable it, use
the `--enable` flag. The following command disables the **edge** repository.
```bash
$ sudo yum-config-manager --disable docker-ce-edge
```
> **Note**: Starting with Docker 17.06, stable releases are also pushed to
> the **edge** and **test** repositories.
[Learn about **stable** and **edge** builds](/engine/installation/).
#### Install Docker CE
1. Install the latest version of Docker CE, or go to the next step to install a
specific version.
```bash
$ sudo yum install docker-ce
```
> **Warning**: If you have multiple Docker repositories enabled, installing
> or updating without specifying a version in the `yum install` or
> `yum update` command will always install the highest possible version,
> which may not be appropriate for your stability needs.
{:.warning}
If this is the first time you are installing a package from a recently added
repository, you will be prompted to accept the GPG key, and
the key's fingerprint will be shown. Verify that the fingerprint is
correct, and if so, accept the key. The fingerprint should match
`060A 61C5 1B55 8A7F 742B 77AA C52F EB6B 621E 9F35`.
Docker is installed but not started. The `docker` group is created, but no
users are added to the group.
2. On production systems, you should install a specific version of Docker CE
instead of always using the latest. List the available versions. This
example uses the `sort -r` command to sort the results by version number,
highest to lowest, and is truncated.
```bash
$ yum list docker-ce --showduplicates | sort -r
docker-ce.x86_64 {{ site.docker_ce_stable_version }}.ce-1.el7.centos docker-ce-stable
```
The contents of the list depend upon which repositories are enabled, and
will be specific to your version of CentOS (indicated by the `.el7` suffix
on the version, in this example). Choose a specific version to install. The
second column is the version string. You can use the entire version string,
but **you need to include at least to the first hyphen**. The third column
is the repository name, which indicates which repository the package is from
and by extension its stability level. To install a specific version, append
the version string to the package name and separate them by a hyphen (`-`).
> **Note**: The version string is the package name plus the version up to
> the first hyphen. In the example above, the fully qualified package name
> is `docker-ce-17.06.1.ce`.
```bash
$ sudo yum install <FULLY-QUALIFIED-PACKAGE-NAME>
```
3. Start Docker.
```bash
$ sudo systemctl start docker
```
4. Verify that `docker` is installed correctly by running the `hello-world`
image.
```bash
$ sudo docker run hello-world
```
This command downloads a test image and runs it in a container. When the
container runs, it prints an informational message and exits.
Docker CE is installed and running. You need to use `sudo` to run Docker
commands. Continue to [Linux postinstall](/engine/installation/linux/linux-postinstall.md) to allow
non-privileged users to run Docker commands and for other optional configuration
steps.
#### Upgrade Docker CE
To upgrade Docker CE, follow the
[installation instructions](#install-docker), choosing the new version you want
to install.
### Install from a package
If you cannot use Docker's repository to install Docker, you can download the
`.rpm` file for your release and install it manually. You will need to download
a new file each time you want to upgrade Docker.
1. Go to
[{{ download-url-base }}/7/x86_64/stable/Packages/]({{ download-url-base }}/7/x86_64/stable/Packages/)
and download the `.rpm` file for the Docker version you want to install.
> **Note**: To install an **edge** package, change the word
> `stable` in the above URL to `edge`.
> [Learn about **stable** and **edge** channels](/engine/installation/).
2. Install Docker CE, changing the path below to the path where you downloaded
the Docker package.
```bash
$ 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.
3. Start Docker.
```bash
$ sudo systemctl start docker
```
4. Verify that `docker` is installed correctly by running the `hello-world`
image.
```bash
$ sudo docker run hello-world
```
This command downloads a test image and runs it in a container. When the
container runs, it prints an informational message and exits.
Docker CE is installed and running. You need to use `sudo` to run Docker commands.
Continue to [Post-installation steps for Linux](/engine/installation/linux/linux-postinstall.md) to allow
non-privileged users to run Docker commands and for other optional configuration
steps.
#### Upgrade Docker CE
To upgrade Docker CE, download the newer package file and repeat the
[installation procedure](#install-from-a-package), using `yum -y upgrade`
instead of `yum -y install`, and pointing to the new file.
{% include install-script.md %}
## Uninstall Docker CE
1. Uninstall the Docker package:
```bash
$ sudo yum remove docker-ce
```
2. Images, containers, volumes, or customized configuration files on your host
are not automatically removed. To delete all images, containers, and
volumes:
```bash
$ sudo rm -rf /var/lib/docker
```
You must delete any edited configuration files manually.
## Next steps
- Continue to [Post-installation steps for Linux](/engine/installation/linux/linux-postinstall.md)
- Continue with the [User Guide](/engine/userguide/index.md).