正在学习Docker Swarm，接触到了Vagrant。Vagrant是一个创建虚拟机的技术，可以把它认为是一个Vmware，它让我们可以通过代码的方式快速地、可重复地创建针对不同虚拟环境的虚拟机，包括Virtualbox、AWS、Docker等。它使得我们可以一次性地、自动创建多个环境相同的虚拟机，对于软件开发和测试尤其有用，以下是在使用过程中常用到的一些基本命令。
1. 显示当前版本
# vagrant --version
Vagrant 2.0.2
2. 列出所有Box
#vagrant box list
iamseth/rhel-7.3 (virtualbox, 1.0.0)
3. 添加一个Box
#vagrant box add [options] <name, url, or path>
1）可以从https://app.vagrantup.com/boxes/search下载各种Vagrant映像文件
#vagrant box add ubuntu/trusty64
2) 通过指定的URL添加远程box
#vagrant box add https://atlas.hashicorp.com/ubuntu/boxes/trusty64
3) 添加一个本地box
命令格式如下
# vagrant box add {box_name} {file_path}
示例如下:
# vagrant box add CentOS7.1 file:///D:/Work/VagrantBoxes/CentOS-7.1.1503-x86_64-netboot.box
4. 初始化一个新VM
# vagrant init ubuntu/trustry64
此命令会在当前目录创建一个名为Vagrantfile的配置文件，内容大致如下：
Vagrant.configure("2") do |config|
config.vm.box = "ubuntu/trusty64"
end
当在此目录启动Vagrant后，Vagrant会从互联网下载“ubuntu/trusty64”这个box到本地，并使用它作为VM的映像。
5. 初始化一个新VM
# vagrant up
如果我们想启动任意VM，首先进入有Vagrantfile配置文件的目录，然后执行上面的命令。控制台的输出通常如下：
Bringing machine 'default' up with 'virtualbox' provider...
==> default: Importing base box 'ubuntu/trusty64'...
==> default: Matching MAC address for NAT networking...
==> default: Checking if box 'ubuntu/trusty64' is up to date...
==> default: Setting the name of the VM: start_default_1518789015107_16928
==> default: Clearing any previously set forwarded ports...
Vagrant is currently configured to create VirtualBox synced folders with
the `SharedFoldersEnableSymlinksCreate` option enabled. If the Vagrant
guest is not trusted, you may want to disable this option. For more
information on this option, please refer to the VirtualBox manual:
https://www.virtualbox.org/manual/ch04.html#sharedfolders
This option can be disabled globally with an environment variable:
VAGRANT_DISABLE_VBOXSYMLINKCREATE=1
or on a per folder basis within the Vagrantfile:
config.vm.synced_folder '/host/path', '/guest/path', SharedFoldersEnableSymlinksCreate: false
==> default: Clearing any previously set network interfaces...
==> default: Preparing network interfaces based on configuration...
default: Adapter 1: nat
==> default: Forwarding ports...
default: 22 (guest) => 2222 (host) (adapter 1)
==> default: Booting VM...
==> default: Waiting for machine to boot. This may take a few minutes...
default: SSH address: 127.0.0.1:2222
default: SSH username: vagrant
default: SSH auth method: private key
default:
default: Vagrant insecure key detected. Vagrant will automatically replace
default: this with a newly generated keypair for better security.
default:
default: Inserting generated public key within guest...
default: Removing insecure key from the guest if it's present...
default: Key inserted! Disconnecting and reconnecting using new SSH key...
==> default: Machine booted and ready!
==> default: Checking for guest additions in VM...
default: The guest additions on this VM do not match the installed version of
default: VirtualBox! In most cases this is fine, but in rare cases it can
default: prevent things such as shared folders from working properly. If you see
default: shared folder errors, please make sure the guest additions within the
default: virtual machine match the version of VirtualBox you have installed on
default: your host and reload your VM.
default:
default: Guest Additions Version: 4.3.36
default: VirtualBox Version: 5.2
==> default: Mounting shared folders...
default: /vagrant => /Users/qianlong/DockerProjects/vagrant/start
6.启用SSH登陆VM
进入Vagrantfile配置文件所在的目录，执行以下命令：
# vagrant ssh
如果需要从虚拟机中退出，直接在虚拟机中的命令行输入exit命令即可
7. 查看VM当前的状态
进入Vagrantfile配置文件所在的目录，执行以下命令：
# vagrant status
如果VM正在运行，你可以在控制台中看到如下信息：
Current machine states:
default running (virtualbox)
The VM is running. To stop this VM, you can run `vagrant halt` to
shut it down forcefully, or you can run `vagrant suspend` to simply
suspend the virtual machine. In either case, to restart it again,
simply run `vagrant up`.
8.关闭VM
进入Vagrantfile配置文件所在的目录，执行以下命令：
# vagrant halt
9.销毁VM
命令格式如下：
vagrant destory [name|id]
示例如下：
# vagrant destroy ubuntu/trusty64
如果我们是使用了默认的虚拟机名"default"，那其实我们可以直接输入如下命令销毁VM
# vagrant desotry
运行结果如下：
default: Are you sure you want to destroy the 'default' VM? [y/N] y
==> default: Forcing shutdown of VM...
==> default: Destroying VM and associated drives...
需要注意的是，我们要慎重使用该命令，该命令会停止VM的运行，并销毁所有在VM中创建的资源
