Get Docker for Red Hat Enterprise Linux
Estimated reading time: 9 minutesTo get started with Docker on Red Hat Enterprise Linux (RHEL), make sure you meet the prerequisites, then install Docker.
Prerequisites
Docker EE repository URL
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.
- Choose Get Details / Setup Instructions within the Docker Enterprise Edition for Red Hat Enterprise Linux section.
- Copy the URL from the field labeled Copy and paste this URL to download your Edition.
Use this URL when you see the placeholder text <DOCKER-EE-URL>
.
To learn more about Docker EE, see Docker Enterprise Edition.
Docker Community Edition (Docker CE) is not supported on Red Hat Enterprise Linux.
OS requirements
To install Docker, you need the 64-bit version of RHEL 7, running on an x86 hardware platform.
In addition, you must use the devicemapper
storage driver. 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.
Uninstall old versions
Older versions of Docker were called docker
or docker-engine
. If these are
installed, uninstall them, along with associated dependencies.
$ 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 EE package is now called docker-ee
.
Install Docker EE
You can install Docker in different ways, depending on your needs:
Most users set up Docker’s repositories 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
Remove any existing Docker repositories from
/etc/yum.repos.d/
.Store two
yum
variables in/etc/yum/vars/
.Store your EE repository URL in
/etc/yum/vars/dockerurl
. Replace<DOCKER-EE-URL>
with the URL you noted down in the prerequisites.$ sudo sh -c 'echo "<DOCKER-EE-URL>/rhel" > /etc/yum/vars/dockerurl'
Store your RHEL version string in
/etc/yum/vars/dockerosversion
. Use the appropriate value from the following table. Most users should use7
.Version string Description 7
Unless you have specific requirements, you should use this version. Dependencies are not locked to specific versions but use the latest available version. 7.3
Dependencies are locked to specific packages for RHEL 7.3. 7.2
Dependencies are locked to specific packages for RHEL 7.2. $ sudo sh -c 'echo "<VERSION-STRING>" > /etc/yum/vars/dockerosversion'
Install required packages.
yum-utils
provides theyum-config-manager
utility, anddevice-mapper-persistent-data
andlvm2
are required by thedevicemapper
storage driver.$ sudo yum install -y yum-utils device-mapper-persistent-data lvm2
Enable the
extras
RHEL repository. This ensures access to thecontainer-selinux
package which is required bydocker-ee
.$ sudo yum-config-manager --enable rhel-7-server-extras-rpms
Depending on cloud provider, you may also need to enable another repository.
For AWS:
$ sudo yum-config-manager --enable rhui-REGION-rhel-server-extras
Note:
REGION
here is literal, and does not represent the region your machine is running in.For Azure:
$ sudo yum-config-manager --enable rhui-rhel-7-server-rhui-extras-rpms
Use the following command to add the stable repository:
$ sudo yum-config-manager \ --add-repo \ <DOCKER-EE-URL>/rhel/docker-ee.repo
Install Docker
Update the
yum
package index.$ 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 matches
DD91 1E99 5A64 A202 E859 07D6 BC14 F10B 6D08 5F96
and if so, accept the key.Install the latest version of Docker EE, or go to the next step to install a specific version.
$ sudo yum -y install docker-ee
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.$ yum list docker-ee.x86_64 --showduplicates |sort -r docker-ee.x86_64 17.03.0.el7 docker-ee-stable
The contents of the list depend upon which repositories you have enabled, and will be specific to your version of RHEL (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 extension its stability level. To install a specific version, append the version string to the package name and separate them by a hyphen (-
):$ sudo yum -y install docker-ee-<VERSION_STRING>
Edit
/etc/docker/daemon.json
. If it does not yet exist, create it. Assuming that the file was empty, add the following contents.{ "storage-driver": "devicemapper" }
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 before starting Docker.Start Docker.
$ sudo systemctl start docker
Verify that Docker EE is installed correctly 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 an informational message and exits.
Docker EE is installed and running. You need to use sudo
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 EE
To upgrade Docker EE, first run sudo yum makecache fast
, then follow the
installation instructions, choosing the new version you want
to install.
Install from a package
If you cannot use the official Docker 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.
Go to the Docker EE repository URL associated with your trial or subscription in your browser. Go to
rhel/7/x86_64/stable-17.03/Packages
and download the.rpm
file for the Docker version you want to install.Note: If you have trouble with
selinux
using the packages under the7
directory, try choosing the version-specific directory instead, such as7.3
.Install Docker EE, changing the path below to the path where you downloaded the Docker package.
$ sudo yum install /path/to/package.rpm
Edit
/etc/docker/daemon.json
. If it does not yet exist, create it. Assuming that the file was empty, add the following contents.{ "storage-driver": "devicemapper" }
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 before starting Docker.Start Docker.
$ sudo systemctl start docker
Verify that
docker
is installed correctly by running thehello-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 an informational message and exits.
Docker EE is installed and running. You need to use sudo
to run Docker
commands. Continue to Post-installation steps for Linux
to allow non-privileged users to run Docker commands and for other optional
configuration steps.
Upgrade Docker EE
To upgrade Docker EE, download the newer package file and repeat the
installation procedure, using yum -y upgrade
instead of yum -y install
, and pointing to the new file.
Uninstall Docker EE
Uninstall the Docker EE package:
$ sudo yum -y remove docker-ee
Images, containers, volumes, or customized configuration files on your host are not automatically removed. To delete all images, containers, and volumes:
$ sudo rm -rf /var/lib/docker
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
Continue with the User Guide.