docs/engine/installation/linux/centos.md

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---
description: Instructions for installing Docker on CentOS
keywords: Docker, Docker documentation, requirements, apt, installation, centos, rpm, install, uninstall, upgrade, update
redirect_from:
- /engine/installation/centos/
title: Get Docker for CentOS
---
{% assign minor-version = "17.03" %}
To get started with Docker on CentOS, make sure you
[meet the prerequisites](#prerequisites), then
[install Docker](#install-docker).
## Prerequisites
### Docker EE customers
To install Docker Enterprise Edition (Docker EE), you need to know the Docker EE
repository URL associated with your trial or subscription. To get this information:
- Go to [https://store.docker.com/?overlay=subscriptions](https://store.docker.com/?overlay=subscriptions).
- Choose **Get Details** / **Setup Instructions** within the
**Docker Enterprise Edition for CentOS** section.
- Copy the URL from the field labeled
**Copy and paste this URL to download your Edition**.
Where the installation instructions differ for Docker EE and Docker CE, use this
URL when you see the placeholder text `<DOCKER-EE-URL>`.
To learn more about Docker EE, see
[Docker Enterprise Edition](https://www.docker.com/enterprise-edition/){: target="_blank" class="_" }.
In addition, you must use the `devicemapper` storage driver if you use Docker EE
or CS-Engine. On production systems, you must use `direct-lvm` mode, which
requires one or more dedicated block devices. Fast storage such as solid-state
media (SSD) is recommended.
### OS requirements
To install Docker, you need the 64-bit version of CentOS 7.
### 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 \
container-selinux \
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`, and
the Docker EE package is now called `docker-ee`.
## Install Docker
You can install Docker 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 and manage
upgrades completely manually. This is useful in situations such as installing
Docker on air-gapped systems with no access to the internet.
### Install using the repository
Before you install Docker 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
Repository set-up instructions are different for [Docker CE](#docker-ce) and
[Docker EE](#docker-ee).
##### Docker CE
{% 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 **edge** builds
as well.
```bash
$ sudo yum-config-manager \
--add-repo \
{{ download-url-base }}/docker-ce.repo
```
3. **Optional**: Enable the **edge** repository. This repository is included
in the `docker.repo` file above but is disabled by default. You can enable
it alongside the stable repository.
```bash
$ sudo yum-config-manager --enable docker-ce-edge
```
You can disable the **edge** 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
```
[Learn about **stable** and **edge** builds](/engine/installation/).
##### Docker EE
1. Remove any existing Docker repositories from `/etc/yum.repos.d/`.
2. Store your Docker EE repository URL in a `yum` variable in `/etc/yum/vars/`.
Replace `<DOCKER-EE-URL>` with the URL you noted down in the
[prerequisites](#prerequisites).
```bash
$ sudo sh -c 'echo "<DOCKER-EE-URL>" > /etc/yum/vars/dockerurl'
```
3. 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
```
4. Use the following command to add the **stable** repository:
```bash
$ sudo yum-config-manager \
--add-repo \
<DOCKER-EE-URL>/docker-ee.repo
```
#### Install Docker
1. Update the `yum` package index.
```bash
$ sudo yum makecache fast
```
If this is the first time you have refreshed the package index since adding
the Docker repositories, 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.
| Docker Edition | Fingerprint |
|----------------|------------------------------------------------------|
| Docker CE | `060A 61C5 1B55 8A7F 742B 77AA C52F EB6B 621E 9F35` |
| Docker EE | `DD91 1E99 5A64 A202 E859 07D6 BC14 F10B 6D08 5F96` |
2. Install the latest version of Docker, or go to the next step to install a
specific version.
| Docker Edition | Command |
|----------------|-------------------------------------|
| Docker CE | `sudo yum install docker-ce` |
| Docker EE | `sudo yum install docker-ee` |
> **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}
3. On production systems, you should install a specific version of Docker
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.
> **Note**: This `yum list` command only shows binary packages. To show
> source packages as well, omit the `.x86_64` from the package name.
```bash
$ yum list docker-ce.x86_64 --showduplicates |sort -r
docker-ce.x86_64 {{ minor-version }}.0.el7 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. 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 (`-`):
| Docker Edition | Command |
|----------------|-----------------------------------------------|
| Docker CE | `sudo yum install docker-ce-<VERSION>` |
| Docker EE | `sudo yum install docker-ee-<VERSION>` |
4. Edit `/etc/docker/daemon.json`. If it does not yet exist, create it. Assuming
that the file was empty, add the following contents.
```json
{
"storage-driver": "devicemapper"
}
```
5. For production systems, you must use `direct-lvm` mode, which requires you
to prepare the block devices. Follow the procedure in the
[devicemapper storage driver guide](/engine/userguide/storagedriver/device-mapper-driver.md#configure-direct-lvm-mode-for-production){: target="_blank" class="_" }
**before starting Docker**.
6. Start Docker.
```bash
$ sudo systemctl start docker
```
7. 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 is installed and running. You need to use `sudo` to run Docker commands.
Continue to [Linux postinstall](linux-postinstall.md) to allow non-privileged
users to run Docker commands and for other optional configuration steps.
#### Upgrade Docker
To upgrade Docker, first run `sudo yum makecache fast`, then 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. This step is different for Docker CE and Docker EE.
- **Docker CE**: 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 > URL to `edge`.
> [Learn about **stable** and **edge** channels](/engine/installation/).
- **Docker EE**: Go to the Docker EE repository URL associated with your
trial or subscription in your browser. Go to
`7/x86_64/stable-{{ minor-version }}/Packages/` and download the `.rpm`
file for the Docker version you want to install.
2. Install Docker, changing the path below to the path where you downloaded
the Docker package.
```bash
$ sudo yum install /path/to/package.rpm
```
3. Edit `/etc/docker/daemon.json`. If it does not yet exist, create it. Assuming
that the file was empty, add the following contents.
```json
{
"storage-driver": "devicemapper"
}
```
4. For production systems, you must use `direct-lvm` mode, which requires you
to prepare the block devices. Follow the procedure in the
[devicemapper storage driver guide](/engine/userguide/storagedriver/device-mapper-driver.md#configure-direct-lvm-mode-for-production){: target="_blank" class="_" }
**before starting Docker**.
5. Start Docker.
```bash
$ sudo systemctl start docker
```
6. 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 is installed and running. You need to use `sudo` to run Docker commands.
Continue to [Post-installation steps for Linux](linux-postinstall.md) to allow
non-privileged users to run Docker commands and for other optional configuration
steps.
#### Upgrade Docker
To upgrade Docker, 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.
## Uninstall Docker
1. Uninstall the Docker package:
| Docker Edition | Command |
|----------------|--------------------------------|
| Docker CE | `sudo yum remove docker-ce` |
| Docker EE | `sudo yum remove docker-ee` |
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
```
3. If desired, remove the `devicemapper` thin pool and reformat the block
devices that were part of it.
You must delete any edited configuration files manually.
## Next steps
- Continue to [Post-installation steps for Linux](linux-postinstall.md)
- Continue with the [User Guide](../../userguide/index.md).