由于在很多情况下需要安装docker的虚拟机或服务器无法访问互联网，因此需要离线安装docker
准备工作
1、一台可以访问互联网的虚拟机或服务器，操作系统不限，改机器可以访问拟安装docker的机器
STEP 1 以下操作在可以访问互联网的机器进行
1、下载安装包 访问https://download.docker.com/linux/static/stable/ 选择合适的版本并下载，笔者用的是 https://download.docker.com/linux/static/stable/x86_64/docker-18.09.6.tgz
STEP 2 将下载的安装包上传到拟安装的机器
STEP 3 以下操作在拟安装的机器上进行
解压缩安装包
tar -zxvf docker-18.09.6.tgz
复制解压缩后的文件到指定文件夹
cp docker/* /usr/bin/
注册编辑docker服务
vim /etc/systemd/system/docker.service
复制下列内容到该文档中
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target
[Service]
Type=notify
# the default is not to use systemd for cgroups because the delegate issues still
# exists and systemd currently does not support the cgroup feature set required
# for containers run by docker
ExecStart=/usr/bin/dockerd
ExecReload=/bin/kill -s HUP $MAINPID
# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
# Uncomment TasksMax if your systemd version supports it.
# Only systemd 226 and above support this version.
#TasksMax=infinity
TimeoutStartSec=0
# set delegate yes so that systemd does not reset the cgroups of docker containers
Delegate=yes
# kill only the docker process, not all processes in the cgroup
KillMode=process
# restart the docker process if it exits prematurely
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s
[Install]
WantedBy=multi-user.target
添加权限后启动
chmod +x /etc/systemd/system/docker.service
重新加载配置文件
systemctl daemon-reload
启动Docker
systemctl start docker
设置开机自启
systemctl enable docker.service
验证是否安装成功
systemctl status docker
docker -v
