一、首先，先检查CentOS版本，保证在CentOS7版本以上，系统内核在3.10以上——

root@somnus# uname -r

3.10.0-693.el7.x86_64

二、卸载旧的docker版本

sudo yum remove docker

docker-client

docker-client-latest

docker-common

docker-latest

docker-latest-logrotate

docker-logrotate

docker-engine

三、安装需要的依赖包

sudo yum install -y yum-utils

四、设置国内镜像的仓库

yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo

yum-config-manager --enable docker-ce-nightly

yum-config-manager --enable docker-ce-test

yum-config-manager --disable docker-ce-nightly

五、更新yum软件包索引

yum install docker-ce docker-ce-cli container

六、启动docker

systemctl start docker

systemctl daemon-reload

systemctl start docker

七、检查docker是否正常

docker version

[root@somnus# docker version

Client: Docker Engine - Community

Version: 20.10.8

API version: 1.41

Go version: go1.16.6

Git commit: 3967b7d

Built: Fri Jul 30 19:55:49 2021

OS/Arch: linux/amd64

Context: default

Experimental: true

Server: Docker Engine - Community

Engine:

Version: 20.10.8

API version: 1.41 (minimum version 1.12)

Go version: go1.16.6

Git commit: 75249d8

Built: Fri Jul 30 19:54:13 2021

OS/Arch: linux/amd64

Experimental: false

containerd:

Version: 1.4.9

GitCommit: e25210fe30a0a703442421b0f60afac609f950a3

runc:

Version: 1.0.1

GitCommit: v1.0.1-0-g4144b63

docker-init:

Version: 0.19.0

GitCommit: de40ad0]

当看到上面所示，那Docker就安装结束了