ubantu下装Docker

Docker 要求 Ubuntu 系统的内核版本高于 3.10 ，查看本页面的前提条件来验证你的 Ubuntu 版本是否支持 Docker。

通过 uname -r 命令查看你当前的内核版本

 uname -r

4.15.0-20-generic

版本是4.15所以就没问题

然后使用脚本安装Docker

1.获取最新版本的Docker安装包

wget -qO- https://get.docker.com/ | sh

安装完会有个提示：

If you would like to use Docker as a non-root user, you should now consider
adding your user to the "docker" group with something like:

  sudo usermod -aG docker limingxing(我的用户名)

Remember that you will have to log out and back in for this to take effect!

当要以非root用户可以直接运行docker时，需要执行 sudo usermod -aG docker runoob 命令（每次都是）

2.启动docker后台服务

 sudo service docker start

3.测试运行hello world

 sudo docker run hello-world

运行结果为(可以好好读一下setps)：

Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
9bb5a5d4561a: Pull complete
Digest: sha256:3e1764d0f546ceac4565547df2ac4907fe46f007ea229fd7ef2718514bcec35d
Status: Downloaded newer image for hello-world:latest

Hello from Docker!
This message shows that your installation appears to be working correctly.

To generate this message, Docker took the following steps:
 . The Docker client contacted the Docker daemon.
 . The Docker daemon pulled the "hello-world" image from the Docker Hub.
    (amd64)
 . The Docker daemon created a new container from that image which runs the
    executable that produces the output you are currently reading.
 . The Docker daemon streamed that output to the Docker client, which sent it
    to your terminal.

To try something more ambitious, you can run an Ubuntu container with:
 $ docker run -it ubuntu bash

Share images, automate workflows, and more with a free Docker ID:
 https://hub.docker.com/

For more examples and ideas, visit:
 https://docs.docker.com/engine/userguide/

鉴于国内网络问题，后续拉取 Docker 镜像十分缓慢，我们可以需要配置加速器来解决，我使用的是网易的镜像地址：http://hub-mirror.c.163.com。

新版的 Docker 使用 /etc/docker/daemon.json（Linux）来配置 Daemon。

请在该配置文件中加入（没有该文件的话，请先建一个）：

{
  "registry-mirrors": ["http://hub-mirror.c.163.com"]
}

4.15.0-20-generic