不是 root 用户，所有命令前添加  sudo

查看当前的内核版本， 官方建议 3.10 以上

uname -r

Uninstall old version

sudo yum remove docker \
                docker-client \
                docker-client-latest \
                docker-common \
                docker-latest \
                docker-latest-logrotate \
                docker-logrotate \
                docker-engine

安装需要的软件包

yum install -y yum-utils device-mapper-persistent-data lvm2

设置yum安装源

yum-config-manager --add-repo http://download.docker.com/linux/centos/docker-ce.repo（中央仓库）
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo（国内建议安装阿里仓库）

查看可用版本有哪些

yum list docker-ce --showduplicates | sort -r

选择一个版本并安装

yum install docker-ce-版本号

yum install -y docker-ce docker-ce-cli http://containerd.io

启动 Docker

systemctl start docker

设置开机自启

systemctl enable docker

测试docker是否安装成功

docker -v

[root@xxxxx~]# docker -v
Docker version 20.10.17, build 100c701
[root@xxxxx ~]# docker version
Client: Docker Engine - Community
 Version:           20.10.17
 API version:       1.41
 Go version:        go1.17.11
 Git commit:        100c701
 Built:             Mon Jun  6 23:03:11 2022
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true
Server: Docker Engine - Community
 Engine:
  Version:          20.10.17
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.17.11
  Git commit:       a89b842
  Built:            Mon Jun  6 23:01:29 2022
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.6.6
  GitCommit:        10c12954828e7c7c9b6e0ea9b0c02b01407d3ae1
 runc:
  Version:          1.1.2
  GitCommit:        v1.1.2-0-ga916309
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0