github.com/akashshinde/docker@v1.9.1/docs/installation/rhel.md (about) 1 <!--[metadata]> 2 +++ 3 title = "Installation on Red Hat Enterprise Linux" 4 description = "Instructions for installing Docker on Red Hat Enterprise Linux." 5 keywords = ["Docker, Docker documentation, requirements, linux, rhel"] 6 [menu.main] 7 parent = "smn_linux" 8 weight = -5 9 +++ 10 <![end-metadata]--> 11 12 # Red Hat Enterprise Linux 13 14 Docker is supported on Red Hat Enterprise Linux 7. This page instructs you to 15 install using Docker-managed release packages and installation mechanisms. Using 16 these packages ensures you get the latest release of Docker. If you wish to 17 install using Red Hat-managed packages, consult your Red Hat release 18 documentation for information on Red Hat's Docker support. 19 20 ## Prerequisites 21 22 Docker requires a 64-bit installation regardless of your Red Hat version. Docker 23 requires that your kernel must be 3.10 at minimum, which Red Hat 7 runs. 24 25 To check your current kernel version, open a terminal and use `uname -r` to 26 display your kernel version: 27 28 $ uname -r 29 3.10.0-229.el7.x86_64 30 31 Finally, is it recommended that you fully update your system. Please keep in 32 mind that your system should be fully patched to fix any potential kernel bugs. 33 Any reported kernel bugs may have already been fixed on the latest kernel 34 packages. 35 36 ## Install Docker Engine 37 38 There are two ways to install Docker Engine. You can install with the `yum` package manager directly yourself. Or you can use `curl` with the `get.docker.com` site. This second method runs an installation script which installs via the `yum` package manager. 39 40 ### Install with yum 41 42 1. Log into your machine as a user with `sudo` or `root` privileges. 43 44 2. Make sure your existing yum packages are up-to-date. 45 46 $ sudo yum update 47 48 3. Add the yum repo yourself. 49 50 $ cat >/etc/yum.repos.d/docker.repo <<-EOF 51 [dockerrepo] 52 name=Docker Repository 53 baseurl=https://yum.dockerproject.org/repo/main/centos/7 54 enabled=1 55 gpgcheck=1 56 gpgkey=https://yum.dockerproject.org/gpg 57 EOF 58 59 4. Install the Docker package. 60 61 $ sudo yum install docker-engine 62 63 5. Start the Docker daemon. 64 65 $ sudo service docker start 66 67 6. Verify `docker` is installed correctly by running a test image in a container. 68 69 $ sudo docker run hello-world 70 Unable to find image 'hello-world:latest' locally 71 latest: Pulling from hello-world 72 a8219747be10: Pull complete 73 91c95931e552: Already exists 74 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. 75 Digest: sha256:aa03e5d0d5553b4c3473e89c8619cf79df368babd1.7.1cf5daeb82aab55838d 76 Status: Downloaded newer image for hello-world:latest 77 Hello from Docker. 78 This message shows that your installation appears to be working correctly. 79 80 To generate this message, Docker took the following steps: 81 1. The Docker client contacted the Docker daemon. 82 2. The Docker daemon pulled the "hello-world" image from the Docker Hub. 83 (Assuming it was not already locally available.) 84 3. The Docker daemon created a new container from that image which runs the 85 executable that produces the output you are currently reading. 86 4. The Docker daemon streamed that output to the Docker client, which sent it 87 to your terminal. 88 89 To try something more ambitious, you can run an Ubuntu container with: 90 $ docker run -it ubuntu bash 91 92 For more examples and ideas, visit: 93 http://docs.docker.com/userguide/ 94 95 ### Install with the script 96 97 You use the same installation procedure for all versions of CentOS. 98 99 1. Log into your machine as a user with `sudo` or `root` privileges. 100 101 2. Make sure your existing yum packages are up-to-date. 102 103 $ sudo yum update 104 105 3. Run the Docker installation script. 106 107 $ curl -sSL https://get.docker.com/ | sh 108 109 4. Start the Docker daemon. 110 111 $ sudo service docker start 112 113 5. Verify `docker` is installed correctly by running a test image in a container. 114 115 $ sudo docker run hello-world 116 117 ## Create a docker group 118 119 The `docker` daemon binds to a Unix socket instead of a TCP port. By default 120 that Unix socket is owned by the user `root` and other users can access it with 121 `sudo`. For this reason, `docker` daemon always runs as the `root` user. 122 123 To avoid having to use `sudo` when you use the `docker` command, create a Unix 124 group called `docker` and add users to it. When the `docker` daemon starts, it 125 makes the ownership of the Unix socket read/writable by the `docker` group. 126 127 >**Warning**: The `docker` group is equivalent to the `root` user; For details 128 >on how this impacts security in your system, see [*Docker Daemon Attack 129 >Surface*](../articles/security.md#docker-daemon-attack-surface) for details. 130 131 To create the `docker` group and add your user: 132 133 1. Log into your machine as a user with `sudo` or `root` privileges. 134 135 2. Create the `docker` group and add your user. 136 137 `sudo usermod -aG docker your_username` 138 139 3. Log out and log back in. 140 141 This ensures your user is running with the correct permissions. 142 143 4. Verify your work by running `docker` without `sudo`. 144 145 $ docker run hello-world 146 147 ## Start the docker daemon at boot 148 149 To ensure Docker starts when you boot your system, do the following: 150 151 $ sudo chkconfig docker on 152 153 If you need to add an HTTP Proxy, set a different directory or partition for the 154 Docker runtime files, or make other customizations, read our Systemd article to 155 learn how to [customize your Systemd Docker daemon options](../articles/systemd.md). 156 157 158 ## Uninstall 159 160 You can uninstall the Docker software with `yum`. 161 162 1. List the package you have installed. 163 164 $ yum list installed | grep docker 165 yum list installed | grep docker 166 docker-engine.x86_64 1.7.1-0.1.el7@/docker-engine-1.7.1-0.1.el7.x86_64 167 168 2. Remove the package. 169 170 $ sudo yum -y remove docker-engine.x86_64 171 172 This command does not remove images, containers, volumes, or user created 173 configuration files on your host. 174 175 3. To delete all images, containers, and volumes run the following command: 176 177 $ rm -rf /var/lib/docker 178 179 4. Locate and delete any user-created configuration files.