首先安装docker-compose
官网：https://docs.docker.com/compose/
(1)创建文件夹
mkdir -p /tmp/composetest cd /tmp/composetest(2)创建app.py文件，写业务内容
import time import redis from flask import Flask app = Flask(__name__) cache = redis.Redis(host='redis', port=6379) def get_hit_count(): retries = 5 while True: try: return cache.incr('hits') except redis.exceptions.ConnectionError as exc: if retries == 0: raise exc retries -= 1 time.sleep(0.5) @app.route('/') def hello(): count = get_hit_count() return 'Hello World! I have been seen {} times.\n'.format(count)(3)新建requirements.txt文件
flask redis(4)编写Dockerfile
FROM python:3.7-alpine WORKDIR /code ENV FLASK_APP app.py ENV FLASK_RUN_HOST 0.0.0.0 RUN apk add --no-cache gcc musl-dev linux-headers COPY requirements.txt requirements.txt RUN pip install -r requirements.txt COPY . . CMD ["flask", "run"](5)根据Dockerfile生成image
docker build -t python-app-image .(6)查看images：docker images
python-app-image latest 7e1d81f366b7 3 minutes ago 213MB(1)创建网络
docker network ls docker network create --subnet=172.20.0.0/24 app-net(1)创建python程序的container，并指定网段和端口
docker run -d --name web -p 5000:5000 --network app-net python-app-image(2)创建redis的container，并指定网段
docker run -d --name redis --network app-net redis:alpineip[centos]:5000
官网：https://docs.docker.com/compose/
Compose is a tool for defining and running multi-container Docker applications. With Compose, you use a YAML file to configure your application’s services. Then, with a single command, you create and start all the services from your configuration.Linux环境中需要单独安装
官网：https://docs.docker.com/compose/install/
sudo curl -L "https://github.com/docker/compose/releases/download/1.24.1/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose sudo chmod +x /usr/local/bin/docker-composereference：https://docs.docker.com/compose/gettingstarted/
新建目录，比如composetest
进入目录，编写app.py代码
创建requirements.txt文件
编写Dockerfile
默认名称，当然也可以指定，docker-compose.yaml
version: '3' services: web: build: . ports: - "5000:5000" networks: - app-net redis: image: "redis:alpine" networks: - app-net networks: app-net: driver: bridge(1)通过docker compose创建容器
docker-compose up -d(2)访问测试
[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-Qrw0GFOC-1603186662966)(D:/work/完成dockerV1.0/images/32.png)]
(1)version: ‘3’
表示docker-compose的版本(2)services
一个service表示一个container(3)networks
相当于docker network create app-net(4)volumes
相当于-v v1:/var/lib/mysql(5)image
表示使用哪个镜像，本地build则用build，远端则用image(6)ports
相当于-p 8080:8080(7)environment
相当于-e(1)查看版本
docker-compose version
(2)根据yml创建service
docker-compose up
指定yaml：docker-compose up -f xxx.yaml
后台运行：docker-compose up
(3)查看启动成功的service
docker-compose ps
也可以使用docker ps
(4)查看images
docker-compose images
(5)停止/启动service
docker-compose stop/start
(6)删除service[同时会删除掉network和volume]
docker-compose down
(7)进入到某个service
docker-compose exec redis sh
(1)修改docker-compose.yaml文件，主要是把web的ports去掉，不然会报错
version: '3' services: web: build: . networks: - app-net redis: image: "redis:alpine" networks: - app-net networks: app-net: driver: bridge(2)创建service
docker-compose up -d(3)若要对python容器进行扩缩容
docker-compose up --scale web=5 -d docker-compose ps docker-compose logs web官网：https://docs.docker.com/swarm/
(1)根据Vagrantfile创建3台centos机器
[大家可以根据自己实际的情况准备3台centos机器，不一定要使用vagrant+virtualbox]
新建swarm-docker-centos7文件夹，创建Vagrantfile
boxes = [ { :name => "manager-node", :eth1 => "192.168.0.11", :mem => "1024", :cpu => "1" }, { :name => "worker01-node", :eth1 => "192.168.0.12", :mem => "1024", :cpu => "1" }, { :name => "worker02-node", :eth1 => "192.168.0.13", :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]] v.customize ["modifyvm", :id, "--name", opts[:name]] end config.vm.network :public_network, ip: opts[:eth1] end end end(2)进入到对应的centos里面，使得root账户能够登陆，从而使用XShell登陆
vagrant ssh manager-node/worker01-node/worker02-node sudo -i vi /etc/ssh/sshd_config 修改PasswordAuthentication yes passwd 修改密码 systemctl restart sshd(3)在win上ping一下各个主机，看是否能ping通
ping 192.168.0.11/12/13(4)在每台机器上安装docker engine
小技巧：要想让每个shell窗口一起执行同样的命令"查看–>撰写–>撰写窗口–>全部会话"
(1)进入manager
提示：manager node也可以作为worker node提供服务
docker swarm init --advertise-addr=192.168.0.11注意观察日志，拿到worker node加入manager node的信息
docker swarm join --token SWMTKN-1-0a5ph4nehwdm9wzcmlbj2ckqqso38pkd238rprzwcoawabxtdq-arcpra6yzltedpafk3qyvv0y3 192.168.0.11:2377(2)进入两个worker
docker swarm join --token SWMTKN-1-0a5ph4nehwdm9wzcmlbj2ckqqso38pkd238rprzwcoawabxtdq-arcpra6yzltedpafk3qyvv0y3 192.168.0.11:2377日志打印
This node joined a swarm as a worker.(3)进入到manager node查看集群状态
docker node ls(4)node类型的转换
可以将worker提升成manager，从而保证manager的高可用
docker node promote worker01-node docker node promote worker02-node #降级可以用demote docker node demote worker01-nodehttp://labs.play-with-docker.com
(1)创建一个tomcat的service
docker service create --name my-tomcat tomcat(2)查看当前swarm的service
docker service ls(3)查看service的启动日志
docker service logs my-tomcat(4)查看service的详情
docker service inspect my-tomcat(5)查看my-tomcat运行在哪个node上
docker service ps my-tomcat日志
ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS u6o4mz4tj396 my-tomcat.1 tomcat:latest worker01-node Running Running 3 minutes ago(6)水平扩展service
docker service scale my-tomcat=3 docker service ls docker service ps my-tomcat日志：可以发现，其他node上都运行了一个my-tomcat的service
[root@manager-node ~]# docker service ps my-tomcat ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS u6o4mz4tj396 my-tomcat.1 tomcat:latest worker01-node Running Running 8 minutes ago v505wdu3fxqo my-tomcat.2 tomcat:latest manager-node Running Running 46 seconds ago wpbsilp62sc0 my-tomcat.3 tomcat:latest worker02-node Running Running 49 seconds ago此时到worker01-node上：docker ps，可以发现container的name和service名称不一样，这点要知道
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES bc4b9bb097b8 tomcat:latest "catalina.sh run" 10 minutes ago Up 10 minutes 8080/tcp my-tomcat.1.u6o4mz4tj3969a1p3mquagxok(7)如果某个node上的my-tomcat挂掉了，这时候会自动扩展
[worker01-node] docker rm -f containerid [manager-node] docker service ls docker service ps my-tomcat(8)删除service
docker service rm my-tomcat业务场景：workpress+mysql实现个人博客搭建
https://hub.docker.com/_/wordpress?tab=description
docker-compose的方式还是在一台机器中，网络这块很清晰
01-创建wordpress-mysql文件夹 mkdir -p /tmp/wordpress-mysql cd /tmp/wordpress-mysql 02-创建docker-compose.yml文件文件内容
version: '3.1' services: wordpress: image: wordpress restart: always ports: - 8080:80 environment: WORDPRESS_DB_HOST: db WORDPRESS_DB_USER: exampleuser WORDPRESS_DB_PASSWORD: examplepass WORDPRESS_DB_NAME: exampledb volumes: - wordpress:/var/www/html db: image: mysql:5.7 restart: always environment: MYSQL_DATABASE: exampledb MYSQL_USER: exampleuser MYSQL_PASSWORD: examplepass MYSQL_RANDOM_ROOT_PASSWORD: '1' volumes: - db:/var/lib/mysql volumes: wordpress: db: 03-根据docker-compose.yml文件创建service docker-compose up -d 04-访问测试 win10浏览器ip[centos]:8080，一直下一步 05-值得关注的点是网络 docker network ls docker network inspect wordpress-mysql_default还是wordpress+mysql的案例，在docker swarm集群中怎么玩呢？
(1)创建一个overlay网络，用于docker swarm中多机通信
【manager-node】 docker network create -d overlay my-overlay-net docker network ls[此时worker node查看不到](2)创建mysql的service
【manager-node】 01-创建service docker service create --name mysql --mount type=volume,source=v1,destination=/var/lib/mysql --env MYSQL_ROOT_PASSWORD=examplepass --env MYSQL_DATABASE=db_wordpress --network my-overlay-net mysql:5.6 02-查看service docker service ls docker service ps mysql(3)创建wordpress的service
01-创建service [注意之所以下面可以通过mysql名字访问，也是因为有DNS解析] docker service create --name wordpress --env WORDPRESS_DB_USER=root --env WORDPRESS_DB_PASSWORD=examplepass --env WORDPRESS_DB_HOST=mysql:3306 --env WORDPRESS_DB_NAME=db_wordpress -p 8080:80 --network my-overlay-net wordpress 02-查看service docker service ls docker service ps mysql 03-此时mysql和wordpress的service运行在哪个node上，这时候就能看到my-overlay-net的网络(4)测试
win浏览器访问ip[manager/worker01/worker02]:8080都能访问成功(5)查看my-overlay-net
docker network inspect my-overlay-net(6)为什么没有用etcd？docker swarm中有自己的分布式存储机制
通过前面的案例我们发现，部署一个wordpress的service，映射到主机的8080端口，这时候通过swarm集群中的任意主机ip:8080都能成功访问，这是因为什么？
把问题简化：docker service create --name tomcat -p 8080:8080 --network my-overlay-net tomcat
(1)记得使用一个自定义的overlay类型的网络
--network my-overlay-net(2)查看service情况
docker service ls docker service ps tomcat(3)访问3台机器的ip:8080测试
发现都能够访问到tomcat的欢迎页之前在实战wordpress+mysql的时候，发现wordpress中可以直接通过mysql名称访问
这样可以说明两点，第一是其中一定有dns解析，第二是两个service的ip是能够ping通的
思考：不妨再创建一个service，也同样使用上述tomcat的overlay网络，然后来实验
docker service create --name whoami -p 8000:8000 --network my-overlay-net -d jwilder/whoami
(1)查看whoami的情况
docker service ps whoami(2)在各自容器中互相ping一下彼此，也就是容器间的通信
#tomcat容器中ping whoami docker exec -it 9d7d4c2b1b80 ping whoami 64 bytes from bogon (10.0.0.8): icmp_seq=1 ttl=64 time=0.050 ms 64 bytes from bogon (10.0.0.8): icmp_seq=2 ttl=64 time=0.080 ms #whoami容器中ping tomcat docker exec -it 5c4fe39e7f60 ping tomcat 64 bytes from bogon (10.0.0.18): icmp_seq=1 ttl=64 time=0.050 ms 64 bytes from bogon (10.0.0.18): icmp_seq=2 ttl=64 time=0.080 ms(3)将whoami进行扩容
docker service scale whoami=3 docker service ps whoami #manager,worker01,worker02(4)此时再ping whoami service，并且访问whoami服务
#ping docker exec -it 9d7d4c2b1b80 ping whoami 64 bytes from bogon (10.0.0.8): icmp_seq=1 ttl=64 time=0.055 ms 64 bytes from bogon (10.0.0.8): icmp_seq=2 ttl=64 time=0.084 ms #访问 docker exec -it 9d7d4c2b1b80 curl whoami:8000 [多访问几次] I'm 09f4158c81ae I'm aebc574dc990 I'm 7755bc7da921小结：通过上述的实验可以发现什么？whoami服务对其他服务暴露的ip是不变的，但是通过whoami名称访问8000端口，确实访问到的是不同的service，就说明访问其实是像下面这张图。
也就是说whoami service对其他服务提供了一个统一的VIP入口，别的服务访问时会做负载均衡。
docker stack deploy：https://docs.docker.com/engine/reference/commandline/stack_deploy/
compose-file：https://docs.docker.com/compose/compose-file/
有没有发现上述部署service很麻烦？要是能够类似于docker-compose.yml文件那种方式一起管理该多少？这就要涉及到docker swarm中的Stack，我们直接通过前面的wordpress+mysql案例看看怎么使用咯。
(1)新建service.yml文件
version: '3' services: wordpress: image: wordpress ports: - 8080:80 environment: WORDPRESS_DB_HOST: db WORDPRESS_DB_USER: exampleuser WORDPRESS_DB_PASSWORD: examplepass WORDPRESS_DB_NAME: exampledb networks: - ol-net volumes: - wordpress:/var/www/html deploy: mode: replicated replicas: 3 restart_policy: condition: on-failure delay: 5s max_attempts: 3 update_config: parallelism: 1 delay: 10s db: image: mysql:5.7 environment: MYSQL_DATABASE: exampledb MYSQL_USER: exampleuser MYSQL_PASSWORD: examplepass MYSQL_RANDOM_ROOT_PASSWORD: '1' volumes: - db:/var/lib/mysql networks: - ol-net deploy: mode: global placement: constraints: - node.role == manager volumes: wordpress: db: networks: ol-net: driver: overlay(2)根据service.yml创建service
docker statck deploy -c service.yml my-service(3)常见操作
01-查看stack具体信息 docker stack ls NAME SERVICES ORCHESTRATOR my-service 2 Swarm 02-查看具体的service docker stack services my-service ID NAME MODE REPLICAS IMAGE PORTS icraimlesu61 my-service_db global 1/1 mysql:5.7 iud2g140za5c my-service_wordpress replicated 3/3 wordpress:latest *:8080->80/tcp 03-查看某个service docker service inspect my-service-db "Endpoint": { "Spec": { "Mode": "vip" }, "VirtualIPs": [ { "NetworkID": "kz1reu3yxxpwp1lvnrraw0uq6", "Addr": "10.0.1.5/24" } ] }(4)访问测试
win浏览器ip[manager,worker01,worker02]:8080
