Docker-Swarm集群

创建环境

1.使用Vagrant方式

　　Vagrantfile文件

Vagrant.require_version ">= 1.6.0"

boxes = [
	{
		:name => "swarm-manager",
		:eth1 => "192.168.88.100",
		:mem => "1024",
		:cpu => "1"
	},
	{
		:name => "swarm-worker1",
		:eth1 => "192.168.88.101",
		:mem => "1024",
		:cpu => "1"
	},
	{
		:name => "swarm-worker2",
		:eth1 => "192.168.88.102",
		:mem => "1024",
		:cpu => "1"
	}
]

Vagrant.configure(2) do |config|

  config.vm.box = "centos/7"

  boxes.each do |opts|
      config.vm.define opts[:name] do |config|
        config.vm.hostname = opts[:name]
        config.vm.provider "vmware_fusion" do |v|
          v.vmx["memsize"] = opts[:mem]
          v.vmx["numvcpus"] = opts[:cpu]
        end

        config.vm.provider "virtualbox" do |v|
          v.customize ["modifyvm", :id, "--memory", opts[:mem]]
          v.customize ["modifyvm", :id, "--cpus", opts[:cpu]]
        end

        config.vm.network :private_network, type: "dhcp"
      end
  end

  config.vm.synced_folder "./labs", "/home/vagrant/labs"
  config.vm.provision "shell", privileged: true, path: "./setup.sh"

end

　　setup.sh文件

#/bin/sh

# install some tools
sudo yum install -y wget
sudo mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
sudo wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
sudo yum makecache
sudo yum -y update
sudo yum install -y git vim gcc glibc-static telnet bridge-utils net-tools

# install docker
sudo curl -fsSL get.docker.com -o get-docker.sh
sudo sh get-docker.sh

# start docker service
sudo groupadd docker
sudo usermod -aG docker vagrant
sudo rm -rf get-docker.sh

sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["https://grlbs31g.mirror.aliyuncs.com"]
}
EOF

sudo systemctl daemon-reload
sudo systemctl start docker
sudo docker version
sudo curl -L "https://github.com/docker/compose/releases/download/1.26.0/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
sudo chmod +x /usr/local/bin/docker-compose
sudo ln -s /usr/local/bin/docker-compose /usr/bin/docker-compose
sudo docker-compose --version

sudo echo "Congratulations on your success!"

　　创建机器

# 先装插件
vagrant plugin install vagrant-vbguest
# Vagrantfile文件所在目录执行
vagrant status
vagrant up

参考：https://github.com/limingios/docker

2. docker-machine方式

　　安装Docker Toolbox

http://mirrors.aliyun.com/docker-toolbox/windows/docker-toolbox/

　　创建机器

docker-machine create swarm-manager
docker-machine create swarm-worker1
docker-machine create swarm-worker2

搭建Swarm集群

# manager
docker swarm init --advertise-addr 192.168.88.100 
# worker1 & worker2
docker swarm join --token SWMTKN-1-1jtoogjh8go3dslv2zfbu7qqiz6xhs28qt3651nrdi206cwobp-e74f0yoqo6nwdxrdj3pfnkwkq 192.168.88.100:2377
# 如果要添加manager2，manager执行
docker swarm join-token manager
# manager2
docker swarm join --token SWMTKN-1-1jtoogjh8go3dslv2zfbu7qqiz6xhs28qt3651nrdi206cwobp-3y38tktkfpq86lhjf2hmswb6f 192.168.88.100:2377
# 查看节点信息
docker node ls

节点支持升级为manager、降级为worker、退出集群
docker node --help
docker swarm --help

　　集群中创建容器

docker service create --name demo busybox sh -c "while true;do sleep 3600;done"
docker service ls
# 查看容器在集群中哪个节点中创建
docker service ps demo
# 横向扩展
docker service scale demo=5
docker service rm demo

　　集群中跨机器的容器间通信

# 创建overlay驱动类型的网络
docker network create -d overlay demo
# 创建MySQL
docker service create --name mysql --network demo --env MYSQL_ROOT_PASSWORD=root --env MYSQL_DATABASE=wordpress --mount type=volume,source=mysql-data,destination=/var/lib/mysql mysql:5.7
# 创建Wordpress
docker service create --name wordpress --network demo -p 80:80 --env WORDPRESS_DB_PASSWORD=root WORDPRESS_DB_HOST=mysql wordpress
# 浏览器访问
192.168.88.100 192.168.88.101 192.168.88.102 都可以访问通

Routing Mesh两种方式　　

　　Internal：容器间通过overlay网络通信（DNS域名解析+VIP虚拟IP+Iptables防火墙+LVS负载均衡）　　　

# 查看DNS对应的VIP
nslookup mysql
# 查看VIP对象的容器真实IP
nslookup tasks.mysql

　　Ingress：如果服务有绑定端口，则通过集群中各个节点IP:Port都可以访问到服务

# swarm-worker1中显示防火墙配置规则
sudo iptables -nL -t nat
# 查看docker_gwbridge网桥对应的接口
sudo brctl show
# 查看docker_gwbridge网桥对应的namespace网络命名空间
sudo docker network inspect docker_gwbridge
# 列举namespace网络命名空间
sudo ls /var/run/docker/netns
# 切换到ingress_sbox网络命名空间中
sudo nsenter --net=/var/run/docker/netns/ingress_sbox
sudo iptables -nL -t mangle
# 切换回swarm-worker1中
sudo yum install -y ipvsadm
# 切换到ingress_sbox网络命名空间中
sudo nsenter --net=/var/run/docker/netns/ingress_sbox
ipvsadm -l

Docker Stack集群环境方式一键部署多个容器

　　docker-compose.yml文件

version: '3'

services:
   web:
      image: wordpress
      ports:
         - 8080:80
      environment:
         WORDPRESS_DB_HOST: mysql
         WORDPRESS_DB_PASSWORD: root
      networks:
         - my-network
      depends_on:
         - mysql
      deploy:
         mode: replicated
         replicas: 3
         restart_policy:
            condition: on-failure
            delay: 30s
            max_attempts: 3
         update_config:
            parallelism: 1
            delay: 10s             
   mysql:
      image: mysql:5.7
      environment:
         MYSQL_ROOT_PASSWORD: root
         MYSQL_DATABASE: wordpress
      volumes:
         - mysql-data:/var/lib/mysql
      networks:
         - my-network
      deploy:
         mode: global
         placement:
            constraints:
               - node.role == manager
               
volumes:
   mysql-data:
   
networks:
   my-network:
      driver: overlay      
     

　　创建服务

docker stack deploy wordpress --compose-file docker-compose.yml
docker stack ls
docker stack ps wordpress
docker stack services wordpress　　　　

复杂的服务

　　参考：https://docs.docker.com/compose/compose-file/#compose-file-structure-and-examples