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To get started with Docker Engine on CentOS, make sure youmeet the prerequisites, theninstall Docker.
Mar 09, 2020 The steps shared here are for the installation of Docker CE on RHEL 7 Linux. Docker is the main dominant container runtime engine used for Development and running of micro-serviced applications in production. There are two editions of Docker available for installation on a RHEL 7 Desktop / Linux machine. Docker Community Edition ( Docker CE). Docker is a daemon-based container engine which allows us to deploy applications inside containers. With the release of RHEL 8 and CentOS 8, docker package has been removed from their default package repositories, docker has been replaced with podman and buildah.
Jan 28, 2018 Install Docker on CentOS # Although the Docker package is available in the official CentOS 7 repository, it may not always be the latest version. The recommended approach is to install Docker from the Docker’s repositories. To install Docker on your CentOS 7 server follow the steps below. The latest release of the RHEL 8 / CentOS 8. Red Hat has built its own tools, buildah and podman, which aim to be compatible with existing docker images and work without relying on a daemon, allowing the creation of containers as normal users, without the need of special permissions (with some limitations: e.g. At the moment of writing, it's still not possible to map host ports to the. Jan 14, 2018 How to install and use Docker CE on a CentOS Linux 7 server? Docker is free and open-source software. It automates the deployment of any application as a lightweight, portable, self-sufficient container that will run virtually anywhere.
To install Docker Engine, you need a maintained version of CentOS 7 or 8.Archived versions aren’t supported or tested.
The centos-extras
repository must be enabled. This repository is enabled bydefault, but if you have disabled it, you need tore-enable it.
The overlay2
storage driver is recommended.
Older versions of Docker were called docker
or docker-engine
. If these areinstalled, uninstall them, along with associated dependencies.
It’s OK if yum
reports that none of these packages are installed.
The contents of /var/lib/docker/
, including images, containers, volumes, andnetworks, are preserved. The Docker Engine package is now called docker-ce
.
You can install Docker Engine in different ways, depending on your needs:
Most usersset up Docker’s repositories and installfrom them, for ease of installation and upgrade tasks. This is therecommended approach.
Some users download the RPM package andinstall it manually and manageupgrades completely manually. This is useful in situations such as installingDocker on air-gapped systems with no access to the internet.
In testing and development environments, some users choose to use automatedconvenience scripts to install Docker.
Before you install Docker Engine for the first time on a new host machine, you needto set up the Docker repository. Afterward, you can install and update Dockerfrom the repository.
Install the yum-utils
package (which provides the yum-config-manager
utility) and set up the stable repository.
Optional: Enable the nightly or test repositories.
These repositories are included in the docker.repo
file above but are disabledby default. You can enable them alongside the stable repository. The followingcommand enables the nightly repository.
To enable the test channel, run the following command:
You can disable the nightly or test repository by running theyum-config-manager
command with the --disable
flag. To re-enable it, usethe --enable
flag. The following command disables the nightly repository.
Learn about nightly and test channels.
Install the latest version of Docker Engine and containerd, or go to the next step to install a specific version:
If prompted to accept the GPG key, verify that the fingerprint matches060A 61C5 1B55 8A7F 742B 77AA C52F EB6B 621E 9F35
, and if so, accept it.
Got multiple Docker repositories?
If you have multiple Docker repositories enabled, installingor updating without specifying a version in the
yum install
oryum update
command always installs the highest possible version,which may not be appropriate for your stability needs.
Docker is installed but not started. The docker
group is created, but no users are added to the group.
To install a specific version of Docker Engine, list the available versionsin the repo, then select and install:
a. List and sort the versions available in your repo. This example sorts results by version number, highest to lowest, and is truncated:
The list returned depends on which repositories are enabled, and is specificto your version of CentOS (indicated by the .el7
suffix in this example).
b. Install a specific version by its fully qualified package name, which is the package name (docker-ce
) plus the version string (2nd column) starting at the first colon (:
), up to the first hyphen, separated by a hyphen (-
). For example, docker-ce-18.09.1
.
Docker is installed but not started. The docker
group is created, but no users are added to the group.
Start Docker.
Verify that Docker Engine is installed correctly by running the hello-world
image.
This command downloads a test image and runs it in a container. When thecontainer runs, it prints an informational message and exits.
Docker Engine is installed and running. You need to use sudo
to run Dockercommands. Continue to Linux postinstall to allownon-privileged users to run Docker commands and for other optional configurationsteps.
To upgrade Docker Engine, follow the installation instructions,choosing the new version you want to install.
If you cannot use Docker’s repository to install Docker, you can download the.rpm
file for your release and install it manually. You need to downloada 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.
Note: To install a nightly or test (pre-release) package,change the word
stable
in the above URL tonightly
ortest
.Learn about nightly and test channels.
Install Docker Engine, changing the path below to the path where you downloadedthe Docker package.
Docker is installed but not started. The docker
group is created, but nousers are added to the group.
Start Docker.
Verify that Docker Engine is installed correctly by running the hello-world
image.
This command downloads a test image and runs it in a container. When thecontainer runs, it prints an informational message and exits.
Docker Engine is installed and running. You need to use sudo
to run Docker commands.Continue to Post-installation steps for Linux to allownon-privileged users to run Docker commands and for other optional configurationsteps.
To upgrade Docker Engine, download the newer package file and repeat theinstallation procedure, using yum -y upgrade
instead of yum -y install
, and pointing to the new file.
Docker provides convenience scripts at get.docker.comand test.docker.com for installing edge andtesting versions of Docker Engine - Community into development environments quickly andnon-interactively. The source code for the scripts is in thedocker-install
repository.Using these scripts is not recommended for productionenvironments, and you should understand the potential risks before you usethem:
root
or sudo
privileges to run. Therefore,you should carefully examine and audit the scripts before running them.This example uses the script at get.docker.com toinstall the latest release of Docker Engine - Community on Linux. To install the latesttesting version, use test.docker.com instead. Ineach of the commands below, replace each occurrence of get
with test
.
Warning:
Always examine scripts downloaded from the internet beforerunning them locally.
If you would like to use Docker as a non-root user, you should now consideradding your user to the “docker” group with something like:
Remember to log out and back in for this to take effect!
Warning:
Adding a user to the “docker” group grants them the ability to run containerswhich can be used to obtain root privileges on the Docker host. Refer toDocker Daemon Attack Surfacefor more information.
Docker Engine - Community is installed. It starts automatically on DEB
-based distributions. OnRPM
-based distributions, you need to start it manually using the appropriatesystemctl
or service
command. As the message indicates, non-root users can’trun Docker commands by default.
Note:
To install Docker without root privileges, seeRun the Docker daemon as a non-root user (Rootless mode).
If you installed Docker using the convenience script, you should upgrade Dockerusing your package manager directly. There is no advantage to re-running theconvenience script, and it can cause issues if it attempts to re-addrepositories which have already been added to the host machine.
Uninstall the Docker Engine, CLI, and Containerd packages:
Images, containers, volumes, or customized configuration files on your hostare not automatically removed. To delete all images, containers, andvolumes:
You must delete any edited configuration files manually.