mirror of
https://github.com/moby/moby.git
synced 2022-11-09 12:21:53 -05:00
192 lines
6.2 KiB
Markdown
192 lines
6.2 KiB
Markdown
<!--[metadata]>
|
|
+++
|
|
aliases = [ "/engine/installation/centos/"]
|
|
title = "Installation on CentOS"
|
|
description = "Instructions for installing Docker on CentOS"
|
|
keywords = ["Docker, Docker documentation, requirements, linux, centos, epel, docker.io, docker-io"]
|
|
[menu.main]
|
|
parent = "engine_linux"
|
|
weight=-4
|
|
+++
|
|
<![end-metadata]-->
|
|
|
|
# CentOS
|
|
|
|
Docker runs on CentOS 7.X. An installation on other binary compatible EL7
|
|
distributions such as Scientific Linux might succeed, but Docker does not test
|
|
or support Docker on these distributions.
|
|
|
|
This page instructs you to install using Docker-managed release packages and
|
|
installation mechanisms. Using these packages ensures you get the latest release
|
|
of Docker. If you wish to install using CentOS-managed packages, consult your
|
|
CentOS documentation.
|
|
|
|
## Prerequisites
|
|
|
|
Docker requires a 64-bit installation regardless of your CentOS version. Also,
|
|
your kernel must be 3.10 at minimum, which CentOS 7 runs.
|
|
|
|
To check your current kernel version, open a terminal and use `uname -r` to
|
|
display your kernel version:
|
|
|
|
$ uname -r
|
|
3.10.0-229.el7.x86_64
|
|
|
|
Finally, it is recommended that you fully update your system. Please keep in
|
|
mind that your system should be fully patched to fix any potential kernel bugs.
|
|
Any reported kernel bugs may have already been fixed on the latest kernel
|
|
packages.
|
|
|
|
## Install
|
|
|
|
There are two ways to install Docker Engine. You can install using the `yum`
|
|
package manager. Or you can use `curl` with the `get.docker.com` site. This
|
|
second method runs an installation script which also installs via the `yum`
|
|
package manager.
|
|
|
|
### Install with yum
|
|
|
|
1. Log into your machine as a user with `sudo` or `root` privileges.
|
|
|
|
2. Make sure your existing yum packages are up-to-date.
|
|
|
|
$ sudo yum update
|
|
|
|
3. Add the yum repo.
|
|
|
|
$ sudo tee /etc/yum.repos.d/docker.repo <<-'EOF'
|
|
[dockerrepo]
|
|
name=Docker Repository
|
|
baseurl=https://yum.dockerproject.org/repo/main/centos/7/
|
|
enabled=1
|
|
gpgcheck=1
|
|
gpgkey=https://yum.dockerproject.org/gpg
|
|
EOF
|
|
|
|
4. Install the Docker package.
|
|
|
|
$ sudo yum install docker-engine
|
|
|
|
5. Start the Docker daemon.
|
|
|
|
$ sudo service docker start
|
|
|
|
6. Verify `docker` is installed correctly by running a test image in a container.
|
|
|
|
$ sudo docker run hello-world
|
|
Unable to find image 'hello-world:latest' locally
|
|
latest: Pulling from hello-world
|
|
a8219747be10: Pull complete
|
|
91c95931e552: Already exists
|
|
hello-world:latest: The image you are pulling has been verified. Important: image verification is a tech preview feature and should not be relied on to provide security.
|
|
Digest: sha256:aa03e5d0d5553b4c3473e89c8619cf79df368babd1.7.1cf5daeb82aab55838d
|
|
Status: Downloaded newer image for 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:
|
|
1. The Docker client contacted the Docker daemon.
|
|
2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
|
|
(Assuming it was not already locally available.)
|
|
3. The Docker daemon created a new container from that image which runs the
|
|
executable that produces the output you are currently reading.
|
|
4. 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
|
|
|
|
For more examples and ideas, visit:
|
|
http://docs.docker.com/userguide/
|
|
|
|
### Install with the script
|
|
|
|
|
|
1. Log into your machine as a user with `sudo` or `root` privileges.
|
|
|
|
2. Make sure your existing yum packages are up-to-date.
|
|
|
|
$ sudo yum update
|
|
|
|
3. Run the Docker installation script.
|
|
|
|
$ curl -fsSL https://get.docker.com/ | sh
|
|
|
|
This script adds the `docker.repo` repository and installs Docker.
|
|
|
|
4. Start the Docker daemon.
|
|
|
|
$ sudo service docker start
|
|
|
|
5. Verify `docker` is installed correctly by running a test image in a container.
|
|
|
|
$ sudo docker run hello-world
|
|
|
|
|
|
## Create a docker group
|
|
|
|
The `docker` daemon binds to a Unix socket instead of a TCP port. By default
|
|
that Unix socket is owned by the user `root` and other users can access it with
|
|
`sudo`. For this reason, `docker` daemon always runs as the `root` user.
|
|
|
|
To avoid having to use `sudo` when you use the `docker` command, create a Unix
|
|
group called `docker` and add users to it. When the `docker` daemon starts, it
|
|
makes the ownership of the Unix socket read/writable by the `docker` group.
|
|
|
|
>**Warning**: The `docker` group is equivalent to the `root` user; For details
|
|
>on how this impacts security in your system, see [*Docker Daemon Attack
|
|
>Surface*](../../security/security.md#docker-daemon-attack-surface) for details.
|
|
|
|
To create the `docker` group and add your user:
|
|
|
|
1. Log into Centos as a user with `sudo` privileges.
|
|
|
|
2. Create the `docker` group.
|
|
|
|
`sudo groupadd docker`
|
|
|
|
3. Add your user to `docker` group.
|
|
|
|
`sudo usermod -aG docker your_username`
|
|
|
|
4. Log out and log back in.
|
|
|
|
This ensures your user is running with the correct permissions.
|
|
|
|
5. Verify your work by running `docker` without `sudo`.
|
|
|
|
$ docker run hello-world
|
|
|
|
## Start the docker daemon at boot
|
|
|
|
To ensure Docker starts when you boot your system, do the following:
|
|
|
|
$ sudo chkconfig docker on
|
|
|
|
If you need to add an HTTP Proxy, set a different directory or partition for the
|
|
Docker runtime files, or make other customizations, read our Systemd article to
|
|
learn how to [customize your Systemd Docker daemon options](../../admin/systemd.md).
|
|
|
|
|
|
## Uninstall
|
|
|
|
You can uninstall the Docker software with `yum`.
|
|
|
|
1. List the package you have installed.
|
|
|
|
$ yum list installed | grep docker
|
|
yum list installed | grep docker
|
|
docker-engine.x86_64 1.7.1-1.el7 @/docker-engine-1.7.1-1.el7.x86_64.rpm
|
|
|
|
2. Remove the package.
|
|
|
|
$ sudo yum -y remove docker-engine.x86_64
|
|
|
|
This command does not remove images, containers, volumes, or user-created
|
|
configuration files on your host.
|
|
|
|
3. To delete all images, containers, and volumes, run the following command:
|
|
|
|
$ rm -rf /var/lib/docker
|
|
|
|
4. Locate and delete any user-created configuration files.
|