How to install Docker in CentOS 7

Docker is a platform that makes it easy to build, deploy and start applications using containers. Developing with Docker also speeds up applications because it shares the kernel and other Linux resources.

In this guide we will see how to install docker on CentOS 7.

Uninstall old Docker versions :

Make sure no docker version is installed on your OS by typing the dnf command below :

[root@docker ~]# sudo yum remove docker docker-client docker-client-latest docker-common docker-latest docker-latest-logrotate docker-logrotate docker-engine
Loaded plugins: fastestmirror
No Match for argument: docker
No Match for argument: docker-client
No Match for argument: docker-client-latest
No Match for argument: docker-common
No Match for argument: docker-latest
No Match for argument: docker-latest-logrotate
No Match for argument: docker-logrotate
No Match for argument: docker-engine
No Packages marked for removal

Update the system :

[root@docker ~]# yum update -y
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
base: mirror.marwan.ma
extras: repo.nixval.com
updates: mirror.marwan.ma
Resolving Dependencies
--> Running transaction check
---> Package bind-export-libs.x86_64 32:9.11.4-26.P2.el7_9.4 will be updated
---> Package bind-export-libs.x86_64 32:9.11.4-26.P2.el7_9.5 will be an update
---> Package device-mapper.x86_64 7:1.02.170-6.el7_9.4 will be updated
---> Package device-mapper.x86_64 7:1.02.170-6.el7_9.5 will be an update
---> Package device-mapper-event.x86_64 7:1.02.170-6.el7_9.4 will be updated
---> Package device-mapper-event.x86_64 7:1.02.170-6.el7_9.5 will be an update
---> Package device-mapper-event-libs.x86_64 7:1.02.170-6.el7_9.4 will be updated
---> Package device-mapper-event-libs.x86_64 7:1.02.170-6.el7_9.5 will be an update
---> Package device-mapper-libs.x86_64 7:1.02.170-6.el7_9.4 will be updated
---> Package device-mapper-libs.x86_64 7:1.02.170-6.el7_9.5 will be an update
---> Package firewalld.noarch 0:0.6.3-12.el7 will be updated
---> Package firewalld.noarch 0:0.6.3-13.el7_9 will be an update
---> Package firewalld-filesystem.noarch 0:0.6.3-12.el7 will be updated

Installer les dépendances :

The next step is to install the dependencies required to install docker :

[root@docker ~]# yum install -y yum-utils device-mapper-persistent-data lvm2
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
base: mirror.marwan.ma
extras: repo.nixval.com
updates: mirror.marwan.ma
Package device-mapper-persistent-data-0.8.5-3.el7_9.2.x86_64 already installed and latest version
Package 7:lvm2-2.02.187-6.el7_9.5.x86_64 already installed and latest version
Resolving Dependencies
--> Running transaction check
---> Package yum-utils.noarch 0:1.1.31-54.el7_8 will be installed
--> Processing Dependency: python-kitchen for package: yum-utils-1.1.31-54.el7_8.noarch
--> Processing Dependency: libxml2-python for package: yum-utils-1.1.31-54.el7_8.noarch
--> Running transaction check
---> Package libxml2-python.x86_64 0:2.9.1-6.el7.5 will be installed
---> Package python-kitchen.noarch 0:1.1.1-5.el7 will be installed
--> Processing Dependency: python-chardet for package: python-kitchen-1.1.1-5.el7.noarch
--> Running transaction check
---> Package python-chardet.noarch 0:2.2.1-3.el7 will be installed
--> Finished Dependency Resolution

Add docker repository

To install docker, you must first add the docker repository with the command below :

[root@docker ~]# yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
Loaded plugins: fastestmirror
adding repo from: https://download.docker.com/linux/centos/docker-ce.repo
grabbing file https://download.docker.com/linux/centos/docker-ce.repo to /etc/yum.repos.d/docker-ce.repo
repo saved to /etc/yum.repos.d/docker-ce.repo

You can see that the repository has been installed correctly :

[root@docker ~]# ll /etc/yum.repos.d/
total 44
-rw-r--r--. 1 root root 1664 Nov 23 10:08 CentOS-Base.repo
-rw-r--r--. 1 root root 1309 Nov 23 10:08 CentOS-CR.repo
-rw-r--r--. 1 root root 649 Nov 23 10:08 CentOS-Debuginfo.repo
-rw-r--r--. 1 root root 314 Nov 23 10:08 CentOS-fasttrack.repo
-rw-r--r--. 1 root root 8515 Nov 23 10:08 CentOS-Vault.repo
-rw-r--r--. 1 root root 616 Nov 23 10:08 CentOS-x86_64-kernel.repo
-rw-r--r--. 1 root root 1919 Apr 12 07:33 docker-ce.repo

Installation :

We can finally install docker with the command below :

[root@docker ~]# yum install docker

Once installed, start docker and put the service in status enabled :

[root@docker ~]# systemctl start docker.service
[root@docker ~]# systemctl enable docker

Install a specific version of docker :

First, list the versions available with the command below :

[root@docker ~]# yum list docker-ce --showduplicates | sort -r
updates: mirror.marwan.ma
This system is not registered with an entitlement server. You can use subscription-manager to register.
: manager
Loading mirror speeds from cached hostfile
Loaded plugins: fastestmirror, product-id, search-disabled-repos, subscription-
extras: repo.nixval.com
docker-ce.x86_64 3:20.10.6-3.el7 docker-ce-stable
docker-ce.x86_64 3:20.10.5-3.el7 docker-ce-stable
docker-ce.x86_64 3:20.10.4-3.el7 docker-ce-stable
docker-ce.x86_64 3:20.10.3-3.el7 docker-ce-stable
docker-ce.x86_64 3:20.10.2-3.el7 docker-ce-stable
docker-ce.x86_64 3:20.10.1-3.el7 docker-ce-stable
docker-ce.x86_64 3:20.10.0-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.9-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.8-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.7-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.6-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.5-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.4-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.3-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.2-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.15-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.14-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.1-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.13-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.12-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.11-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.10-3.el7 docker-ce-stable
docker-ce.x86_64 3:19.03.0-3.el7 docker-ce-stable

This command displays the versions available on the repository we have installed.

yum install docker-ce-<VERSION STRING>

Example :

[root@docker ~]# yum install docker-ce-17.06.2.ce

Docker test :

Check that docker has been installed correctly with the command below :

[root@docker ~]# docker run hello-world
Unable to find image 'hello-world:latest' locally
Trying to pull repository docker.io/library/hello-world 
latest: Pulling from docker.io/library/hello-world
b8dfde127a29: Pull complete
Digest: sha256:f2266cbfc127c960fd30e76b7c792dc23b588c0db76233517e1891a4e357d519
Status: Downloaded newer image for docker.io/hello-world:latest
Hello from Docker!
This message shows that your installation appears to be working correctly.
To generate this message, Docker took the following steps:
The Docker client contacted the Docker daemon.
The Docker daemon pulled the "hello-world" image from the Docker Hub.
(amd64)
The Docker daemon created a new container from that image which runs the
executable that produces the output you are currently reading.
The Docker daemon streamed that output to the Docker client, which sent it
to your terminal.
To try something more ambitious, you can run an Ubuntu container with:
$ docker run -it ubuntu bash
Share images, automate workflows, and more with a free Docker ID:
https://hub.docker.com/
For more examples and ideas, visit:
https://docs.docker.com/get-started/