vagrant+virtualbox方式创建一个centeros7

下载安装vagrant

1. 访问Vagrant官网           https://www.vagrantup.com/
2. 点击Download          Windows，MacOS，Linux等
3. 选择对应的版本
4. 傻瓜式安装
5. 命令行输入vagrant，测试是否安装成功

下载安装virtual box

1. 访问VirtualBox官网    https://www.virtualbox.org/
2. 选择左侧的“Downloads”
3.  选择对应的操作系统版本
4. 傻瓜式安装
5. [win10中若出现]安装virtualbox快完成时立即回滚，并提示安装出现严重错误 

        (1)打开服务 

        (2)找到Device Install Service和Device Setup Manager，然后启动 

        (3)再次尝试安装

安装centos7

1. 创建centos7文件夹，并进入其中[目录全路径不要有中文字符]
2. 在此目录下打开cmd，运行vagrant init centos/7

        此时会在当前目录下生成Vagrantfile，同时指定使用的镜像为centos/7，关键是这个镜像在哪里，我已经提前准备好              了，名称是virtualbox.box文件

     3. 将virtualbox.box文件添加到vagrant管理的镜像中

        (1)下载网盘中的virtualbox.box文件
        (2)保存到磁盘的某个目录，比如D:\virtualbox.box
        (3)添加镜像并起名叫centos/7：vagrant box add centos/7 D:\virtualbox.box
        (4)vagrant box list  查看本地的box[这时候可以看到centos/7]

     4.centos/7镜像有了，根据Vagrantfile文件启动创建虚拟机

        来到centos7文件夹，在此目录打开cmd窗口，执行vagrant up[打开virtual box观察，可以发现centos7创建成功]

      5.以后大家操作虚拟机，还是要在centos文件夹打开cmd窗口操作

         vagrant halt   优雅关闭
         vagrant up     正常启动

vagrant常用命令

    (1)vagrant ssh    
        进入刚才创建的centos7中
    (2)vagrant status
        查看centos7的状态
    (3)vagrant halt
        停止/关闭centos7
    (4)vagrant destroy
        删除centos7
    (5)vagrant status
        查看当前vagrant创建的虚拟机
    (6)Vagrantfile中也可以写脚本命令，使得centos7更加丰富
        但是要注意，修改了Vagrantfile，要想使正常运行的centos7生效，必须使用vagrant reload

通过Xshell连接centos7

使用centos7的默认账号连接
    在centos文件夹下执行vagrant ssh-config
    关注:Hostname  Port  IdentityFile
    IP:127.0.0.1
    port:2222
    用户名:vagrant
    密码:vagrant
    文件:Identityfile指向的文件private-key
    
使用root账户登录
    vagrant ssh   进入到虚拟机中
    sudo -i
    vi /etc/ssh/sshd_config
    修改PasswordAuthentication yes
    passwd修改密码，比如abc123
    systemctl restart sshd
    使用账号root，密码abc123进行登录

box的打包分发

01 退出虚拟机
    vagrant halt

02 打包
    vagrant package --output first-docker-centos7.box
    
03 得到first-docker-centos7.box
    
04 将first-docker-centos7.box添加到其他的vagrant环境中
    vagrant box add first-docker-centos7 first-docker-centos7.box
    
05 得到Vagrantfile
    vagrant init first-docker-centos7

06 根据Vagrantfile启动虚拟机
    vagrant up [此时可以得到和之前一模一样的环境，但是网络要重新配置]

Vagrantfile通用写法

# -*- mode: ruby -*-
# vi: set ft=ruby :

# All Vagrant configuration is done below. The "2" in Vagrant.configure
# configures the configuration version (we support older styles for
# backwards compatibility). Please don't change it unless you know what
# you're doing.
Vagrant.configure("2") do |config|
  # The most common configuration options are documented and commented below.
  # For a complete reference, please see the online documentation at
  # https://docs.vagrantup.com.

  # Every Vagrant development environment requires a box. You can search for
  # boxes at https://vagrantcloud.com/search.
  config.vm.box = "centos/7"

  # Disable automatic box update checking. If you disable this, then
  # boxes will only be checked for updates when the user runs
  # `vagrant box outdated`. This is not recommended.
  # config.vm.box_check_update = false

  # Create a forwarded port mapping which allows access to a specific port
  # within the machine from a port on the host machine. In the example below,
  # accessing "localhost:8080" will access port 80 on the guest machine.
  # NOTE: This will enable public access to the opened port
  # config.vm.network "forwarded_port", guest: 80, host: 8080

  # Create a forwarded port mapping which allows access to a specific port
  # within the machine from a port on the host machine and only allow access
  # via 127.0.0.1 to disable public access
  # config.vm.network "forwarded_port", guest: 80, host: 8080, host_ip: "127.0.0.1"

  # Create a private network, which allows host-only access to the machine
  # using a specific IP.
  # config.vm.network "private_network", ip: "192.168.33.10"

  # Create a public network, which generally matched to bridged network.
  # Bridged networks make the machine appear as another physical device on
  # your network.
  config.vm.network "public_network"

  # Share an additional folder to the guest VM. The first argument is
  # the path on the host to the actual folder. The second argument is
  # the path on the guest to mount the folder. And the optional third
  # argument is a set of non-required options.
  # config.vm.synced_folder "../data", "/vagrant_data"

  # Provider-specific configuration so you can fine-tune various
  # backing providers for Vagrant. These expose provider-specific options.
  # Example for VirtualBox:
  #
  # config.vm.provider "virtualbox" do |vb|
  #   # Display the VirtualBox GUI when booting the machine
  #   vb.gui = true
  #
  #   # Customize the amount of memory on the VM:
  #   vb.memory = "1024"
  # end
    config.vm.provider "virtualbox" do |vb|
        vb.memory = "3000"
        vb.name= "caojiulu-centos7"
        vb.cpus= 2
    end
  #
  # View the documentation for the provider you are using for more
  # information on available options.

  # Enable provisioning with a shell script. Additional provisioners such as
  # Puppet, Chef, Ansible, Salt, and Docker are also available. Please see the
  # documentation for more information about their specific syntax and use.
  # config.vm.provision "shell", inline: <<-SHELL
  #   apt-get update
  #   apt-get install -y apache2
  # SHELL
end