docker下载地址：
https://download.docker.com/linux/static/stable/
所有版本都有，根据你的需求去选择。我这里下载的docker版本号是20.10.23
# wget https://download.docker.com/linux/static/stable/x86_64/docker-20.10.23.tgz
# tar zxvf docker-20.10.23.tgz
# cp docker/* /usr/bin/
# vim /etc/systemd/system/docker.service (创建配置文件)配置内容如下：
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target
[Service]
Type=notify
ExecStart=/usr/bin/dockerd --selinux-enabled=false --insecure-registry=127.0.0.1
ExecReload=/bin/kill -s HUP $MAINPID
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
TimeoutStartSec=0
Delegate=yes
KillMode=process
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s
[Install]
WantedBy=multi-user.target 执行如下命令：
# chmod +x /etc/systemd/system/docker.service
# systemctl daemon-reload
# systemctl start docker
# systemctl enable docker
# docker --version
Docker version 20.10.23, build 7155243配置加速器加速下载docker镜像
vim /etc/docker/daemon.json
{
"registry-mirrors": ["https://gg3gwnry.mirror.aliyuncs.com"]
}重启服务：
systemctl daemon-reload
systemctl restart docker