Docker的安装和测试

1，Docker安装

Docker是啥，以及其与虚拟机的对比，就不介绍了，网上有很多资源可以学习和了解。 
本篇文章重点介绍Docker的安装和测试使用。

• Docker的安装，分为离线安装和在线安装两种方式，方便不同的应用场景使用不同的安装方式。
• 关于Docker的测试使用，本文会介绍如何运行Docker容器、如何修改Docker容器，以及如何完成Docker容器到Docker镜像的转化。

1.1，docker离线安装

很简单，从官网下载最新的docker离线安装包，并安装。

# wget https://apt.dockerproject.org/repo/pool/main/d/docker-engine/docker-engine_17.05.0~ce-0~ubuntu-trusty_amd64.deb
# wget http://archive.ubuntu.com/ubuntu/pool/main/libt/libtool/libltdl7_2.4.6-0.1_amd64.deb
# dpkg -i *.deb

1.2，docker在线安装

通过apt-get安装

# cat /etc/issue
Ubuntu 14.04.5 LTS \n \l
# uname -r
4.4.0-81-generic
# sudo apt-get update # 更新系统资源列表
# apt-get -y install docker.io  # 安装docker
# docker -v # 查看docker版本信息
Docker version 1.6.2, build 7c8fca2

通过daocloud安装docker

# curl -sSL https://get.daocloud.io/docker | sh
# docker -v
Docker version 17.06.0-ce, build 02c1d87

通过阿里云的镜像仓库安装docker

# curl -sSL http://acs-public-mirror.oss-cn-hangzhou.aliyuncs.com/docker-engine/internet | sh -
# docker -v
Docker version 17.05.0-ce, build 89658be

1.3，执行docker，验证docker是否安装成功

# docker
Usage:  docker COMMAND

A self-sufficient runtime for containers

Options:
      --config string      Location of client config files (default "/root/.docker")
  -D, --debug              Enable debug mode
      --help               Print usage
  -H, --host list          Daemon socket(s) to connect to
  -l, --log-level string   Set the logging level ("debug"|"info"|"warn"|"error"|"fatal") (default "info")
      --tls                Use TLS; implied by --tlsverify
      --tlscacert string   Trust certs signed only by this CA (default "/root/.docker/ca.pem")
      --tlscert string     Path to TLS certificate file (default "/root/.docker/cert.pem")
      --tlskey string      Path to TLS key file (default "/root/.docker/key.pem")
      --tlsverify          Use TLS and verify the remote
  -v, --version            Print version information and quit

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1.4，用户权限修改

安装成功之后，需要使用root用户才能执行docker命令。 
如果希望用非root用户执行docker命令，可以执行以下语句。 
注意：执行完成后，需要退出再登陆才能生效。

# sudo usermod -aG docker $your-user

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2，术语介绍

Docker有仓库Repositories、镜像Images和容器Container三大核心，三者可以互相转化。

• Docker，平台工具、守护进程
• Image，镜像，包括应用及系统的只读数据包
• Container，容器，虚拟机的运行实例
• Registry，仓库登记，管理镜像文件
• Docker hub，Docker官方公有仓库

三大核心的关系，如下图所示：

3，创建镜像

Docker镜像的创建方式有两种，分别是：

• 基于现有的镜像修改
• 直接创建新镜像

本文介绍基于已有的镜像修改的方式，一共分为五步。

3.1，第一步，下载官网的基础镜像

从官网上pull镜像hello-world，并运行

root@apple:/home/kevin/docker# docker run hello-world
Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
b04784fba78d: Pull complete
Digest: sha256:f3b3b28a45160805bb16542c9531888519430e9e6d6ffc09d72261b0d26ff74f
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:
 1. The Docker client contacted the Docker daemon.
 2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
 3. The Docker daemon created a new container from that image which runs the
    executable that produces the output you are currently reading.
 4. 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://cloud.docker.com/

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

从官网上pull镜像ubuntu，并以交互方式运行

root@apple:/home/kevin/docker# docker run -it ubuntu bash
Unable to find image 'ubuntu:latest' locally
latest: Pulling from library/ubuntu
e0a742c2abfd: Pull complete
486cb8339a27: Pull complete
dc6f0d824617: Pull complete
4f7a5649a30e: Pull complete
672363445ad2: Pull complete
Digest: sha256:84c334414e2bfdcae99509a6add166bbb4fa4041dc3fa6af08046a66fed3005f
Status: Downloaded newer image for ubuntu:latest
root@93a1b9d39683:/#
root@93a1b9d39683:/#
root@93a1b9d39683:/#
root@93a1b9d39683:/#
root@93a1b9d39683:/#

3.2，第二步，在CONTAINER中执行软件的安装

安装Linux基础软件

在第一步的基础上，在容器里面，用root用户执行Linux基础软件的安装。

root@93a1b9d39683:/home# apt-get update
Get:1 http://archive.ubuntu.com/ubuntu xenial InRelease [247 kB]
Get:2 http://security.ubuntu.com/ubuntu xenial-security InRelease [102 kB]
Get:3 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [102 kB]
Get:4 http://security.ubuntu.com/ubuntu xenial-security/universe Sources [42.0 kB]
Get:5 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages [384 kB]
Get:6 http://archive.ubuntu.com/ubuntu xenial-backports InRelease [102 kB]
Get:7 http://archive.ubuntu.com/ubuntu xenial/universe Sources [9802 kB]
Get:8 http://security.ubuntu.com/ubuntu xenial-security/restricted amd64 Packages [12.8 kB]
Get:9 http://security.ubuntu.com/ubuntu xenial-security/universe amd64 Packages [178 kB]
Get:10 http://security.ubuntu.com/ubuntu xenial-security/multiverse amd64 Packages [2931 B]
Get:11 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages [1558 kB]
Get:12 http://archive.ubuntu.com/ubuntu xenial/restricted amd64 Packages [14.1 kB]
Get:13 http://archive.ubuntu.com/ubuntu xenial/universe amd64 Packages [9827 kB]
Get:14 http://archive.ubuntu.com/ubuntu xenial/multiverse amd64 Packages [176 kB]
Get:15 http://archive.ubuntu.com/ubuntu xenial-updates/universe Sources [207 kB]
Get:16 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages [742 kB]
Get:17 http://archive.ubuntu.com/ubuntu xenial-updates/restricted amd64 Packages [13.3 kB]
Get:18 http://archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages [640 kB]
Get:19 http://archive.ubuntu.com/ubuntu xenial-updates/multiverse amd64 Packages [16.8 kB]
Get:20 http://archive.ubuntu.com/ubuntu xenial-backports/main amd64 Packages [4930 B]
Get:21 http://archive.ubuntu.com/ubuntu xenial-backports/universe amd64 Packages [6237 B]
Fetched 24.2 MB in 12min 34s (32.1 kB/s)
Reading package lists... Done

root@93a1b9d39683:/home# apt-get install vim
root@93a1b9d39683:/home# apt-get install curl
root@93a1b9d39683:/home# apt-get install openssh-server
root@93a1b9d39683:/home# apt-get install python 

# 安装ifconfig、netstat
root@93a1b9d39683:/home# apt-get install net-tools

# 安装ping
root@93a1b9d39683:/home# apt-get install iputils-ping

退出CONTAINER

• ctrl+d，退出容器且关闭，docker ps查看容器已退出运行（Exited）
• ctrl+p，ctrl+q，退出容器但不关闭，docker ps查看容器依然处于Up状态

3.3，第三步，将CONTAINER保存为IMAGE

查看容器列表

root@apple:/home/kevin/docker# docker ps -a
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS                     PORTS               NAMES
966bd52b72da        ubuntu              "/bin/sh -c 'while..."   3 hours ago         Exited (137) 2 hours ago                       stupefied_knuth
568e5204fff3        ubuntu              "/bin/sh -c 'while..."   4 hours ago         Exited (137) 2 hours ago                       kind_khorana
00f561d97811        ubuntu              "/bin/echo hello w..."   4 hours ago         Exited (0) 4 hours ago                         nifty_mcnulty
93a1b9d39683        ubuntu              "bash"                   4 hours ago         Up 3 hours                                     zealous_noether
abdc084f9821        hello-world         "/hello"                 4 hours ago         Exited (0) 3 hours ago                         sleepy_clarke
51097978fdc6        hello-world         "/hello"                 4 hours ago         Exited (0) 3 hours ago                         vibrant_panini

查看镜像列表

root@apple:/home/kevin/docker# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
ubuntu              latest              14f60031763d        3 days ago          120MB
hello-world         latest              1815c82652c0        5 weeks ago         1.84kB

保存容器到镜像

root@apple:/home/kevin/docker# docker commit 93a1b9d39683 learn/visual_init:v1
sha256:56a4eab7dc5b9c1b0dca010e36f4e792963a213ad4b362ab4662602eb66f0216

==============
Usage: docker commit [OPTIONS] CONTAINER [REPOSITORY[:TAG]]Create a new image from a container's changes

  -a, --author=""     Author (e.g., "John Hannibal Smith <[e-mail]>")
  -m, --message=""    Commit message
  -p, --pause=true    Pause container during commit
==============

查看镜像列表

root@apple:/home/kevin/docker# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
learn/visual_init   v1                  56a4eab7dc5b        39 seconds ago      321MB
ubuntu              latest              14f60031763d        3 days ago          120MB
hello-world         latest              1815c82652c0        5 weeks ago         1.84kB

附，容器的常用操作

root@apple:/home/kevin/docker# docker attach $CONTAINER_ID #连接一个已存在的docker容器
root@apple:/home/kevin/docker# docker stop $CONTAINER_ID #停止docker容器
root@apple:/home/kevin/docker# docker start $CONTAINER_ID #启动docker容器
root@apple:/home/kevin/docker# docker restart $CONTAINER_ID #重启docker容器
root@apple:/home/kevin/docker# docker kill $CONTAINER_ID #强制关闭docker容器
root@apple:/home/kevin/docker# docker logs $CONTAINER_ID #查看docker容器运行日志，确保正常运行
root@apple:/home/kevin/docker# docker inspect $CONTAINER_ID #查看container的属性，比如ip等等
root@apple:/home/kevin/docker# docker rm $CONTAINER_ID      # 删除容器

3.4，第四步，将IMAGE上传到仓库，或者保存为本地离线文件

push image到阿里云的私有镜像仓库

# docker login --username=[e-mail] registry.cn-beijing.aliyuncs.com
# docker tag 56a4eab7dc5b registry.cn-beijing.aliyuncs.com/zhangsp/aiwen:visual_init
# docker push registry.cn-beijing.aliyuncs.com/zhangsp/aiwen:visual_init

上传成功，如下图所示

保存docker image为本地文件，然后，可以在其他机器上还原使用

root@apple:/home/kevin# docker images
REPOSITORY                                       TAG                 IMAGE ID            CREATED             SIZE
learn/visual_init                                v1                  56a4eab7dc5b        3 minutes ago       321MB
registry.cn-beijing.aliyuncs.com/zhangsp/aiwen   visual_init         56a4eab7dc5b        3 minutes ago       321MB
ubuntu                                           latest              14f60031763d        3 days ago          120MB
hello-world                                      latest              1815c82652c0        5 weeks ago         1.84kB

# 将docker image保存为离线的本地文件，执行docker save image_name > ./save.tar 或者 docker save -o filepath image_name
root@apple:/home/kevin/docker# docker save -o visual_init.tar 56a4eab7dc5b
root@apple:/home/kevin/docker# ll
total 344956
drwxrwxr-x  2 kevin kevin      4096 Jul 24 08:14 ./
drwxr-xr-x 14 kevin kevin      4096 Jul 24 03:07 ../
-rw-rw-r--  1 kevin kevin  19182004 May  5 13:03 docker-engine_17.05.0~ce-0~ubuntu-trusty_amd64.deb
-rw-rw-r--  1 kevin kevin     38292 Feb  7  2016 libltdl7_2.4.6-0.1_amd64.deb
-rw-------  1 root           root           333993472 Jul 24 08:13 visual_init.tar

3.5，第五步，在其他机器上还原IMAGE测试使用

• 加载一个docker镜像文件，执行docker load -i filepath 或者 docker load < ./save.tar
• 执行docker pull 或者 docker run，运行仓库的image镜像

aiwen@703:~$ docker pull registry.cn-beijing.aliyuncs.com/zhangsp/aiwen:visual_init
visual_init: Pulling from zhangsp/aiwen
e0a742c2abfd: Pull complete
486cb8339a27: Pull complete
dc6f0d824617: Pull complete
4f7a5649a30e: Pull complete
672363445ad2: Pull complete
6f2c8900b1ea: Pull complete
Digest: sha256:faf4284d0980958df3c10c49efcc09a041dc894edd54e29304fb7fbe97c674dc
Status: Downloaded newer image for registry.cn-beijing.aliyuncs.com/zhangsp/aiwen:visual_init

• 备注：导入IMAGE之后，可以通过docker tag命令对IMAGE打标签

kevin@　　　　　　　　

4，参考页面

• 离线安装docker 
  http://blog.csdn.net/wn527518/article/details/53160116
• 通过daocloud在线安装docker 
  http://get.daocloud.io/#install-docker
• 通过阿里云的镜像仓库安装docker 
  http://mirrors.aliyun.com/help/docker-engine?spm=a2c1q.8351553.0.0.468c7ecbF2260n
• 时速云 
  https://www.tenxcloud.com/caas.html
• 网易云 
  https://c.163.com/
• 腾讯云的容器服务 
  https://cloud.tencent.com/product/ccs
• 百度云的容器服务 
  https://cloud.baidu.com/product/bae.html 
  https://cloud.baidu.com/doc/BAE-Pro/GUIGettingStarted.html#.E8.87.AA.E5.AE.9A.E4.B9.89.E9.95.9C.E5.83.8F
• docker的版本升级记录 
  https://github.com/moby/moby/releases
• Docker之常用命令 
  http://blog.chinaunix.net/uid-10915175-id-4443127.html