#将其他的yum源删除
rm -rf /etc/yum.repos.d/*
#使用阿里云的yum源
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

#清除缓存
yum clean all
#更新缓存
yum makecache

#安装docker
yum install docker -y

#重启docker
systemctl start docker

#开机自启动docker
systemctl enable docker

#查看docker 详细信息
docker version
Client: Docker Engine - Community
 Version:           20.10.2
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        2291f61
 Built:             Mon Dec 28 16:17:48 2020
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.2
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.13.15
  Git commit:       8891c58
  Built:            Mon Dec 28 16:16:13 2020
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.4.3
  GitCommit:        269548fa27e0089a8b8278fc4fc781d7f65a939b
 runc:
  Version:          1.0.0-rc92
  GitCommit:        ff819c7e9184c13b7c2607fe6c30ae19403a7aff
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0xxxxxxxxxx [root@liuhang yum.repos.d]# docker versionClient: Docker Engine - Community Version:           20.10.2 API version:       1.41 Go version:        go1.13.15 Git commit:        2291f61 Built:             Mon Dec 28 16:17:48 2020 OS/Arch:           linux/amd64 Context:           default Experimental:      trueServer: Docker Engine - Community Engine:  Version:          20.10.2  API version:      1.41 (minimum version 1.12)  Go version:       go1.13.15  Git commit:       8891c58  Built:            Mon Dec 28 16:16:13 2020  OS/Arch:          linux/amd64  Experimental:     false containerd:  Version:          1.4.3  GitCommit:        269548fa27e0089a8b8278fc4fc781d7f65a939b runc:  Version:          1.0.0-rc92  GitCommit:        ff819c7e9184c13b7c2607fe6c30ae19403a7aff docker-init:  Version:          0.19.0  GitCommit:        de40ad0docker version

#拉取一个叫 hello-world的镜像
[root@VM-0-16-centos ~]# docker pull hello-world
Using default tag: latest
Trying to pull repository library/hello-world ... 
latest: Pulling from library/hello-world
0e03bdcc26d7: Pull complete

#启动这个镜像  出现下面的样子即安装成功
docker run hello-world                   
Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
0e03bdcc26d7: Pull complete 
Digest: sha256:31b9c7d48790f0d8c50ab433d9c3b7e17666d6993084c002c2ff1ca09b96391d
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.
    (amd64)
 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 ID:
 https://hub.docker.com/

For more examples and ideas, visit:
 https://docs.docker.com/get-started/


#使用阿里云镜像加速 
mkdir -p /etc/docker
rm -rf /etc/docker/daemon.json
cat >>/etc/docker/daemon.json<<eof
{
  "registry-mirrors": ["https://5ke62mgb.mirror.aliyuncs.com"]
}
eof
systemctl daemon-reload
systemctl restart docker

安装完成！！！！！