1.設定yum映象

國外的映象安裝速度很慢，採用清華大學 TUNA 映象源。
用root使用者新建 /etc/yum.repos.d/docker.repo 檔案，內容如下：

[dockerrepo]
name=Docker Repository
baseurl=https://mirrors.tuna.tsinghua.edu.cn/docker/yum/repo/centos7
enabled=1
gpgcheck=1
gpgkey=https://mirrors.tuna.tsinghua.edu.cn/docker/yum/gpg

2.安裝

執行命令：

sudo yum makecache
sudo
 
 yum install docker-engine

3.啟動docker服務

執行命令：

systemctl start docker.service

4.測試docker服務

執行命令：

docker run hello-world

螢幕上如果輸出以下類似資訊，說明docker安裝正常。

Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
c04b14da8d14: Pull complete 
Digest: sha256:0256e8
 
a36e2070f7bf2d0b0763dbabdd67798512411de4cdcf9431a1feb60fd9
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.
 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

Share images, automate workflows, and more with a free Docker Hub account:
 https://hub.docker.com

For more examples and ideas, visit:
 https://docs.docker.com/engine/userguide/

5.安裝docker-compose

執行命令：

sudo curl -L https://github.com/docker/compose/releases/download/1.8.1/docker-compose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose

chmod +x /usr/local/bin/docker-compose