docker-machine 创建swarm集群

1、安装virtualbox
在/etc/yum.repos.d/目录下新建virtualbox.repo
写入：

[virtualbox]
name=Oracle Linux / RHEL / CentOS-$releasever / $basearch - VirtualBox
baseurl=http://download.virtualbox.org/virtualbox/rpm/el/$releasever/$basearch
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://www.virtualbox.org/download/oracle_vbox.asc

执行安装命令

#更新yum缓存
yum clean all
yum makecache
#查找适合自己版本的virtualbox
yum  search VirtualBox
# 安装
VirtualBox-5.2.x86_64

2. 安装docker-machine
   官方指导安装docker-machine
   官方centos安装docker

1、安装docker
2、执行如下：
base=https://github.com/docker/machine/releases/download/v0.16.0 &&
  curl -L $base/docker-machine-$(uname -s)-$(uname -m) >/tmp/docker-machine &&
  sudo install /tmp/docker-machine /usr/local/bin/docker-machine

3、 使用docker-machine创建两台虚拟机

$ docker-machine create --driver virtualbox myvm1
$ docker-machine create --driver virtualbox myvm2
$ docker-machine ls
NAME    ACTIVE   DRIVER       STATE     URL                         SWARM   DOCKER        ERRORS
myvm1   -        virtualbox   Running   tcp://192.168.99.100:2376           v17.06.2-ce
myvm2   -        virtualbox   Running   tcp://192.168.99.101:2376           v17.06.2-ce

• 如果出现This computer doesn't have VT-X/AMD-v enabled. Enabling it in the BIOS is mandatory 则需要重启进入bios设置Intel Virtualization Technology设置成abled即可。

4. 通过这两台启动swarm集群，myvm1作为管理节点，myvm2作为工作节点第一台机器充当管理器，执行管理命令并验证工作人员加入群，第二台是工作人员。

使用docker-machine ssh向VM发送命令。 
docker swarm init可以指定myvm1成为一个swarm管理节点
执行命令参考如下：
$ docker-machine ssh myvm1 "docker swarm init --advertise-addr 192.168.99.104:2377"  
Swarm initialized: current node (x500bs7lrweto9chkg6xq2ybd) is now a manager.
To add a worker to this swarm, run the following command:
docker swarm join \  
--token SWMTKN-1-197eaghawf5wqunblowkmgwjojv38ugtmscs943xrrz0jk6bpc-4uor1vdi4cleb5kqq2ri7s17g \  
192.168.99.104:2377                                                                                                                                                                                                                                                                                                                                                   To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions. 
将myvm2   作为工作节点加入swarm
$ docker-machine ssh myvm2 "docker swarm join \                                                                                                                             --token SWMTKN-1-197eaghawf5wqunblowkmgwjojv38ugtmscs943xrrz0jk6bpc-4uor1vdi4cleb5kqq2ri7s17g \                                                                                >     192.168.99.104:2377" 
This node joined a swarm as a worker. 

参考官方：https://docs.docker.com/get-started/part4/#deploy-your-app-on-the-swarm-cluster