docker的官网：

官网：https://www.docker.com
文档地址：https://docs.docker.com 超级详细的docker文档
仓库地址：https://hub.docker.com push pull 镜像发布

1 环境准备

# 查看系统内核和操作系统版本
[root@test239 yum.repos.d]# uname -r
4.18.0-193.el8.x86_64
[root@test239 yum.repos.d]# cat /etc/redhat-release 
CentOS Linux release 8.2.2004 (Core) 

配置CentOS8的yum源，参考：https://www.jianshu.com/p/fd0aca9c89f8

2 安装

查看官方帮助文档：https://docs.docker.com/engine/install/centos/

2.1 卸载旧版本docker

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

2.2 通过yum安装

#通过yum命令安装
[root@test239 /]# yum install -y yum-utils

# 设置镜像仓库，添加阿里云镜像地址，官网给的镜像地址访问太慢
[root@test239 /]#  yum-config-manager   --add-repo   http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

Adding repo from: http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo


# 更新yum软件包索引
[root@test238 ~]# yum makecache

# 安装最新版的docker  docker-ce（ce表示是社区版，ee表示是企业版）
[root@test239 /]# yum install docker-ce docker-ce-cli containerd.io docker-compose-plugin

2.3 确认是否安装成功

[root@test239 /]# docker --version
Docker version 20.10.17, build 100c701

3 启动运行

[root@test239 /]# systemctl status docker
● docker.service - Docker Application Container Engine
   Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)
   Active: active (running) since Mon 2022-06-27 09:59:36 CST; 8s ago
     Docs: https://docs.docker.com
 Main PID: 1941544 (dockerd)

4 运行helloworld

[root@test239 /]# docker run hello-world
Unable to find image 'hello-world:latest' locally     #本地没有找到hello-world的镜像
latest: Pulling from library/hello-world      # 去下载最新的hello-world镜像
2db29710123e: Pull complete     #下载成功
Digest: sha256:13e367d31ae85359f42d637adf6da428f76d75dc9afeb3c21faea0d976f5c651
Status: Downloaded newer image for hello-world:latest

Hello from Docker!           #看见这句，说明docker已安装成功
This message shows that your installation appears to be working correctly.

使用docker images 命令查看下载的镜像
可以看到上面下载的hello-world镜像

[root@test239 /]# docker images
REPOSITORY    TAG       IMAGE ID       CREATED        SIZE
hello-world   latest    feb5d9fea6a5   9 months ago   13.3kB

问题记录1： centos8 安装docker报错

[root@test239 /]# yum install docker-ce docker-ce-cli containerd.io docker-compose-plugin
Last metadata expiration check: 0:01:05 ago on Mon 27 Jun 2022 09:24:54 AM CST.
Error: 
 Problem 1: problem with installed package podman-1.6.4-10.module_el8.2.0+305+5e198a41.x86_64
  - package podman-1.6.4-10.module_el8.2.0+305+5e198a41.x86_64 requires runc >= 1.0.0-57, but none of the providers can be installed
  - package podman-3.3.1-9.module_el8.5.0+988+b1f0b741.x86_64 requires runc >= 1.0.0-57, but none of the providers can be installed
  - package containerd.io-1.6.6-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.6.6-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.6.6-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.6.6-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - cannot install the best candidate for the job
  - package runc-1.0.0-66.rc10.module_el8.5.0+1004+c00a74f5.x86_64 is filtered out by modular filtering
  - package runc-1.0.0-72.rc92.module_el8.5.0+1006+8d0e68a2.x86_64 is filtered out by modular filtering
 Problem 2: problem with installed package buildah-1.11.6-7.module_el8.2.0+305+5e198a41.x86_64
  - package buildah-1.11.6-7.module_el8.2.0+305+5e198a41.x86_64 requires runc >= 1.0.0-26, but none of the providers can be installed
  - package buildah-1.22.3-2.module_el8.5.0+911+f19012f9.x86_64 requires runc >= 1.0.0-26, but none of the providers can be installed
  - package docker-ce-3:20.10.17-3.el8.x86_64 requires containerd.io >= 1.4.1, but none of the providers can be installed
  - package containerd.io-1.4.10-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.10-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.11-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.11-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.12-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.12-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.13-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.13-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.3-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.3-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.3-3.2.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.3-3.2.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.4-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.4-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.6-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.6-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.8-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.8-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.9-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.4.9-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.5.10-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.5.10-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.5.11-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.5.11-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.6.4-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.6.4-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.6.6-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - package containerd.io-1.6.6-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.2-1.module_el8.5.0+911+f19012f9.x86_64
  - cannot install the best candidate for the job
  - package containerd.io-1.4.10-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.10-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.11-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.11-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.12-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.12-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.13-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.13-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.3-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.3-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.3-3.2.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.3-3.2.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.4-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.4-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.6-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.6-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.8-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.8-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.9-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.4.9-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.5.10-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.5.10-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.5.11-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.5.11-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.6.4-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.6.4-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.6.6-3.1.el8.x86_64 conflicts with runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package containerd.io-1.6.6-3.1.el8.x86_64 obsoletes runc provided by runc-1.0.0-65.rc10.module_el8.2.0+305+5e198a41.x86_64
  - package runc-1.0.0-56.rc5.dev.git2abd837.module_el8.3.0+569+1bada2e4.x86_64 is filtered out by modular filtering
  - package runc-1.0.0-66.rc10.module_el8.5.0+1004+c00a74f5.x86_64 is filtered out by modular filtering
  - package runc-1.0.0-72.rc92.module_el8.5.0+1006+8d0e68a2.x86_64 is filtered out by modular filtering
(try to add '--allowerasing' to command line to replace conflicting packages or '--skip-broken' to skip uninstallable packages or '--nobest' to use not only best candidate packages)

原因
因为centos8默认使用podman代替docker，直接安装docker会产生冲突，执行下面的命令，移除podman

yum erase podman buildah