容器编排Docker Swarm

1. Docker Swarm介绍
2. 安装
3. 创建一个三节点的swarm集群
4. Service的创建维护和水平扩展
5. swarm集群里通过service部署wordpress
- 创建网络
- 创建service容器
6. 集群服务间通信之Routing mesh
- Routing Mesh的两种体现
  - Internal
  - Ingress
7. Docker Stack部署Wordpress
8. Docker Secret管理和使用
cat /run/secrets/my-pw
mysql -u root -p
- 9. Service更新

1. Docker Swarm介绍

怎么去管理多个容器？
怎么能去方便横向扩展
如果容器down了，怎么能自动恢复？
如何去更新容器而不影响业务？
如何去监控追踪这些容器？
怎么去调度容器的创建？
保护隐私数据？

Docker Swarm就是为了解决这些等等问题而诞生的。

Docker Swarm两种角色Manager与Worker

Docker Swarm两种概念Service和Replicas

一个Service代表一个container，这个container可以从dockerhub拉取的image创建，或者从本地的Dockerfile build出来的image创建
Replicas表示横向扩展，一个Replicas表示横向扩展一个容器

一个nginx的Service横向扩展三个Replicas，上图实际过程中会产生三个容器，这三个容器会通过我们的调度系统计算哪一个node负载较轻，然后调度到不同的node上面去。

swarm 服务创建和调度的过程

2. 安装

Docker Swarm 由docker公司开发，存在于docker中，安装好docker docker swarm也就安装好了。

3. 创建一个三节点的swarm集群

使用Vagrantfile创建

Vagrantfile文件

# -*- mode: ruby -*-
# vi: set ft=ruby :
Vagrant.require_version ">= 1.6.0"
boxes = [
    {
        :name => "swarm-manager",
        :eth1 => "192.168.205.10",
        :mem => "1024",
        :cpu => "1"
    },
    {
        :name => "swarm-worker1",
        :eth1 => "192.168.205.11",
        :mem => "1024",
        :cpu => "1"
    },
    {
        :name => "swarm-worker2",
        :eth1 => "192.168.205.12",
        :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, ip: opts[:eth1]
      end
  end
  config.vm.synced_folder "./labs", "/home/vagrant/labs"
  config.vm.provision "shell", privileged: true, path: "./setup.sh"
end

创建虚拟主机

192:chapter7 webxudong$ vagrant up
192:chapter7 webxudong$ vagrant status
Current machine states:

swarm-manager             running (virtualbox)
swarm-worker1             running (virtualbox)
swarm-worker2             running (virtualbox)

This environment represents multiple VMs. The VMs are all listed
above with their current state. For more information about a specific
VM, run `vagrant status NAME`.

进入三台虚拟主机

192:chapter7 webxudong$ vagrant ssh swarm-manager
[vagrant@swarm-manager ~]$ 

192:chapter7 webxudong$ vagrant ssh swarm-worker1
[vagrant@swarm-worker1 ~]$ 

192:chapter7 webxudong$ vagrant ssh swarm-worker2
[vagrant@swarm-worker2 ~]$

三台虚拟主机初始化docker swarm

swarm-manager节点上运行 ```sh [vagrant@swarm-manager ~]$ docker swarm init —advertise-addr 192.168.205.10 Swarm initialized: current node (j60cxemf5q7twe6p65qpzhpv4) is now a manager.

To add a worker to this swarm, run the following command:

docker swarm join --token SWMTKN-1-07gcjx7j45mcjut8aswso26hb5x1futswqbua47pt6b1ik2xlq-aazwz5ra9z4v4erxr8qzixp1o 192.168.205.10:2377

To add a manager to this swarm, run ‘docker swarm join-token manager’ and follow the instructions.


- swarm-worker1节点上运行
```sh
[vagrant@swarm-worker1 ~]$ docker swarm join --token SWMTKN-1-07gcjx7j45mcjut8aswso26hb5x1futswqbua47pt6b1ik2xlq-aazwz5ra9z4v4erxr8qzixp1o 192.168.205.10:2377
This node joined a swarm as a worker.

swarm-worker1节点上运行

[vagrant@swarm-worker2 ~]$ docker swarm join --token SWMTKN-1-07gcjx7j45mcjut8aswso26hb5x1futswqbua47pt6b1ik2xlq-aazwz5ra9z4v4erxr8qzixp1o 192.168.205.10:2377
This node joined a swarm as a worker.

swarm-manager节点上查看swarm集群

[vagrant@swarm-manager ~]$ docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
j60cxemf5q7twe6p65qpzhpv4 *   swarm-manager       Ready               Active              Leader              19.03.5
j362tummq26toh1sr6rfarfl0     swarm-worker1       Ready               Active                                  19.03.5
o59j6gjuy45p9ix1rlv127bdx     swarm-worker2       Ready               Active                                  19.03.5

4. Service的创建维护和水平扩展

创建Service

swarm-manager节点上运行

[vagrant@swarm-manager ~]$ docker service create --name demo busybox sh -c "while true;do sleep 3600;done"
[vagrant@swarm-manager ~]$ docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
24jntr5hdpxp        demo                replicated          1/1                 busybox:latest 
# 查看demo container运行在哪个node
[vagrant@swarm-manager ~]$ docker service ps demo
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
ivvn28n2ss52        demo.1              busybox:latest      swarm-manager       Running             Running about a minute ago 
[vagrant@swarm-manager ~]$ docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
24jntr5hdpxp        demo                replicated          1/1                 busybox:latest

MODE: 模式 REPLICAS: 水平扩展 1/1 分母表示水平扩展个数，分子表示运行的个数

Service水平扩展

swarm-manager节点上运行

[vagrant@swarm-manager ~]$ docker service scale demo=5
demo scaled to 5
overall progress: 5 out of 5 tasks 
1/5: running   [==================================================>] 
2/5: running   [==================================================>] 
3/5: running   [==================================================>] 
4/5: running   [==================================================>] 
5/5: running   [==================================================>] 
verify: Service converged 
[vagrant@swarm-manager ~]$ docker service ps demo
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE            ERROR               PORTS
ivvn28n2ss52        demo.1              busybox:latest      swarm-manager       Running             Running 13 minutes ago                       
u5typ20d0y4v        demo.2              busybox:latest      swarm-worker2       Running             Running 11 seconds ago                       
ialhh3zp6j44        demo.3              busybox:latest      swarm-worker2       Running             Running 11 seconds ago                       
ujz455zw5e72        demo.4              busybox:latest      swarm-manager       Running             Running 24 seconds ago                       
aqoucqu52nhp        demo.5              busybox:latest      swarm-worker1       Running             Running 10 seconds ago

通过NODE节点观察，可发现有水平扩展后的5个demo container，2个在swarm-manager节点上，2个在swarm-worker2节点上，1个在swarm-worker1节点上。

swarm-worker2节点上运行

[vagrant@swarm-manager ~]$ docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS               NAMES
f4081ed632ba        busybox:latest      "sh -c 'while true;d…"   6 minutes ago       Up 6 minutes                            demo.4.ujz455zw5e7223txnxv9s7ppw
284153a86f6b        busybox:latest      "sh -c 'while true;d…"   20 minutes ago      Up 20 minutes                           demo.1.ivvn28n2ss52uzeryn9nodkm1
# 在swarm-worker2 node上强制删除一个demo container
[vagrant@swarm-worker2 ~]$ docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS               NAMES
a915a5b0b425        busybox:latest      "sh -c 'while true;d…"   9 minutes ago       Up 8 minutes                            demo.2.u5typ20d0y4vqn2kky0c7r2ib
7356c9c03d67        busybox:latest      "sh -c 'while true;d…"   9 minutes ago       Up 8 minutes                            demo.3.ialhh3zp6j44mbojzyv82j84l
[vagrant@swarm-worker2 ~]$ docker rm -f 7356c9c03d67
7356c9c03d67

swarm-manager节点上运行

[vagrant@swarm-manager ~]$ docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
24jntr5hdpxp        demo                replicated          5/5                 busybox:latest  
[vagrant@swarm-manager ~]$ docker service ps demo
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE            ERROR                         PORTS
ivvn28n2ss52        demo.1              busybox:latest      swarm-manager       Running             Running 23 minutes ago                                 
u5typ20d0y4v        demo.2              busybox:latest      swarm-worker2       Running             Running 9 minutes ago                                  
rhsryeg7n21u        demo.3              busybox:latest      swarm-worker1       Running             Running 21 seconds ago                                 
ialhh3zp6j44         \_ demo.3          busybox:latest      swarm-worker2       Shutdown            Failed 26 seconds ago    "task: non-zero exit (137)"   
ujz455zw5e72        demo.4              busybox:latest      swarm-manager       Running             Running 9 minutes ago                                  
aqoucqu52nhp        demo.5              busybox:latest      swarm-worker1       Running             Running 9 minutes ago

可以观察出我们在swarm-worker2上删除一个demo container之后，在swarm-worker1上多出了一个demo container。 这就说明swarm scale不仅可以做到横向扩展，而且可以确保我们一定数目的扩展是有效的。

删除Service

swarm-manager节点上运行

[vagrant@swarm-manager ~]$ docker service rm demo
demo
[vagrant@swarm-manager ~]$ docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS

5. swarm集群里通过service部署wordpress

创建网络

在swarm-manager节点上创建一个overlay的网络，使集群之间的container网络互通

[vagrant@swarm-manager ~]$ docker network create -d overlay demo
jd53h59af2rjd12t0s7ibuwha
[vagrant@swarm-manager ~]$ docker network ls
NETWORK ID          NAME                DRIVER              SCOPE
fbbe012e1221        bridge              bridge              local
jd53h59af2rj        demo                overlay             swarm
594d137fcf21        docker_gwbridge     bridge              local
1df5f5c0357a        host                host                local
m0nxe0fd0k7p        ingress             overlay             swarm
8b8926c5e805        none                null                local

创建service容器

在swarm-manager节点上创建mysql容器

[vagrant@swarm-manager ~]$ docker service create --name mysql --env MYSQL_ROOT_PASSWORD=root --env MYSQL_DATABASE=wordpress --network demo --mount type=volume,source=mysql-data,destination=/var/lib/mysql mysql:5.7
[vagrant@swarm-manager ~]$ docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
5veg8wfapdki        mysql               replicated          1/1                 mysql:latest        
[vagrant@swarm-manager ~]$ docker service ps mysql
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE           ERROR               PORTS
vpgxe1saj60e        mysql.1             mysql:latest        swarm-manager       Running             Running 2 minutes ago

在swarm-manager节点上创建wordpress容器

# 这里 WORDPRESS_DB_HOST 地址一定要填写Container容器的名称来访问。
[vagrant@swarm-manager ~]$ docker service create --name wordpress -p 80:80 --env WORDPRESS_DB_PASSWORD=root --env WORDPRESS_DB_HOST=mysql:3306 --network demo wordpress
[vagrant@swarm-manager ~]$ docker service ps wordpress
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
pb8xcsubwxrc        wordpress.1         wordpress:latest    swarm-worker1       Running             Running about a minute ago

访问测试

输入任意虚拟主机IP地址即可访问例如： 192.168.250.11

6. 集群服务间通信之Routing mesh

swarm集群之间的通信主要是由Routing Mesh实现的。实例：第5点的创建网络

Routing Mesh的两种体现

`Internal`

Internal — Container和Container之间的访问通过overlay网络（通过VIP也就是虚拟IP）,然后经过LVS映射到具体哪一个node的Container上访问。已达到负载均衡。

`Ingress`

Ingress — 如果服务有绑定接口，则此服务可以通过任意swarm节点的相应接口访问。

比如A、B两个node做了swarm集群，若A node有一个开放了8080端口的容器，则通过B node的8080端口也可以进行访问。

Ingress的三个特性

外部访问的负载均衡
服务端口被暴露到各个swarm节点
内部通过IPVS进行负载均衡

VIP:10.0.9.4
web:10.0.9.4
web.1
web.2
client
10.0.9.5
10.0.9.3
10.0.9.6
DNSServer
DNSServer
DNSServer
Swarm-manager
Swarm-worker1
Swarm-worker2

上图表示当一个request请求到host3节点时，因为host3没有对应的服务容器，所以host3节点的IPV6就会将该请求转发到有服务容器的host2节点进行处理请求并返回消息。

具体讲解：https://coding.imooc.com/lesson/189.html#mid=11817

7. Docker Stack部署Wordpress

Docker Compose方式部署Docker Swarm集群

官方文档: https://docs.docker.com/compose/compose-file/#deploy

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: 5s
        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

mode: 模式，global（swarm集群只有一个容器）或replicated（容器的指定数量）。默认值为replicated。 constraints: 指定容器存放在哪一个节点 replicas: 初始化容器的数量 restart_policy: 配置是否以及如何在容器退出时重新启动容器

condition：重启策略，none，on-failure（如果失败就重启）或者any（默认值：any）。
delay：尝试重新启动等待的时间（默认值：0）。
max_attempts：在放弃之前尝试重新启动容器的次数（默认值：never give up）。如果在配置的window内重新启动未成功，则此尝试不计入配置的max_attempts值。例如，如果max_attempts设置为“ 2”，并且第一次尝试时重新启动失败，则可能会尝试两次以上的重新启动。
window：决定重新启动是否成功之前要等待的时间，指定为持续时间（默认值：立即决定）。

update_config: 配置应如何更新服务。

parallelism: 一次更新的容器数量。
delay: 更新一组容器之间的等待时间。
failure_action:如果更新失败该怎么办。 continue, rollback, or pause之一 (default: pause).
monitor: 每个任务更新后监视失败的持续时间 (ns|us|ms|s|m|h) (default 0s).
max_failure_ratio: 更新期间容忍的失败率。
order: 更新期间的操作顺序. One of stop-first (旧任务在启动新任务之前停止), or start-first (新任务先启动与正在运行的任务短暂重叠) (默认 stop-first) Note: Only supported for v3.4 and higher

[vagrant@swarm-manager wordpress]$ ll
-rw-r--r--. 1 vagrant vagrant 797 11月  9 01:36 docker-compose.yml

定义一个stack

在swarm-manager虚拟机上运行

#wordpress 表示stack的name        --compose-file可简化为-c
[vagrant@swarm-manager wordpress]$ docker stack deploy wordpress --compose-file=docker-compose.yml
Creating network wordpress_my-network
Creating service wordpress_web
Creating service wordpress_mysql
[vagrant@swarm-manager wordpress]$ docker stack ls
NAME                SERVICES            ORCHESTRATOR
wordpress           2                   Swarm
[vagrant@swarm-manager wordpress]$ docker stack ps wordpress
ID                  NAME                                        IMAGE               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
lrrljhecevie        wordpress_mysql.j60cxemf5q7twe6p65qpzhpv4   mysql:5.7           swarm-manager       Running             Running about a minute ago                       
lv8pp54nocv5        wordpress_web.1                             wordpress:latest    swarm-worker2       Running             Running about a minute ago                       
4e5n61cxluc8        wordpress_web.2                             wordpress:latest    swarm-manager       Running             Running 17 seconds ago                           
j5ygi22idfa9        wordpress_web.3                             wordpress:latest    swarm-worker1       Running             Running about a minute ago                       
[vagrant@swarm-manager wordpress]$ docker stack services wordpress
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
5dvzninwbelp        wordpress_web       replicated          3/3                 wordpress:latest    *:8080->80/tcp
kn54k9wirhi6        wordpress_mysql     global              1/1                 mysql:5.7

访问测试

输入三台虚拟主机任意ip即可例如：http://192.168.205.12:8080/

删除stack

[vagrant@swarm-manager wordpress]$ docker stack rm wordpress
Removing service wordpress_mysql
Removing service wordpress_web
Removing network wordpress_my-network
[vagrant@swarm-manager wordpress]$ docker stack ls
NAME                SERVICES            ORCHESTRATOR

8. Docker Secret管理和使用

什么是Secret

用户名密码
SSH key
TLS认证
任何不想让人看到的数据

Secret Management

存在Swarm Manager节点 Raft database里。
Secret可以assign给一个service，这个service就能看到这个secret
在container内部Secret看起来像文件，但实际是存在内存中的

创建Secret

文件创建（swarm-manager node）

# password 的内容为 admin123
[vagrant@swarm-manager wordpress]$ vim password
[vagrant@swarm-manager wordpress]$ docker secret create my-pw password
k2cdynlhfrndmmmzsdy8ypu08
[vagrant@swarm-manager wordpress]$ rm -rf password 
[vagrant@swarm-manager wordpress]$ docker secret ls
ID                          NAME                DRIVER              CREATED             UPDATED
k2cdynlhfrndmmmzsdy8ypu08   my-pw                                   42 seconds ago      42 seconds ago

标准输入创建（swarm-manager node）

[vagrant@swarm-manager wordpress]$ echo "adminadmin" | docker secret create my-pw2 -
44jotpnunsf6g6r08p5aych2g
[vagrant@swarm-manager wordpress]$ docker secret ls
ID                          NAME                DRIVER              CREATED             UPDATED
k2cdynlhfrndmmmzsdy8ypu08   my-pw                                   2 minutes ago       2 minutes ago
44jotpnunsf6g6r08p5aych2g   my-pw2                                  3 seconds ago       3 seconds ago

删除secret（swarm-manager node）

[vagrant@swarm-manager wordpress]$ docker secret rm my-pw2
my-pw2
[vagrant@swarm-manager wordpress]$ docker secret ls
ID                          NAME                DRIVER              CREATED             UPDATED
k2cdynlhfrndmmmzsdy8ypu08   my-pw                                   3 minutes ago       3 minutes ago

使用secret

示例（swarm-manager node）

# 传入多个secret时 指定多个--secret即可 如：--secret my-pw --secret my-pw2
[vagrant@swarm-manager wordpress]$ docker service create --name client --secret my-pw busybox sh -c "while true;do sleep 3600; done"
[vagrant@swarm-manager wordpress]$ docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
fxhh0c9onw2i        client              replicated          1/1                 busybox:latest      
[vagrant@swarm-manager wordpress]$ docker service ps client
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
t7n08iczw9cz        client.1            busybox:latest      swarm-manager       Running             Running about a minute ago                       
[vagrant@swarm-manager wordpress]$ docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED              STATUS              PORTS               NAMES
7d8245e2a1ed        busybox:latest      "sh -c 'while true;d…"   About a minute ago   Up About a minute                       client.1.t7n08iczw9czjb3y0tpuxvox4
[vagrant@swarm-manager wordpress]$ docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED              STATUS              PORTS               NAMES
7d8245e2a1ed        busybox:latest      "sh -c 'while true;d…"   About a minute ago   Up About a minute                       client.1.t7n08iczw9czjb3y0tpuxvox4
#进入容器 查看secret
[vagrant@swarm-manager wordpress]$ docker exec -it 7d82 sh
/ # cd /run/secrets/
/run/secrets # ls
my-pw
/run/secrets # cat my-pw
admin123

实例: mysql

创建db容器（swarm-manager node）

[vagrant@swarm-manager wordpress]$ docker service create --name db --secret my-pw -e MYSQL_ROOT_PASSWORD_FILE=/run/secrets/my-pw mysql:5.7
nsk6nxis00y2iwqbmhkv99voz
overall progress: 1 out of 1 tasks 
1/1: running   [==================================================>] 
verify: Service converged 
[vagrant@swarm-manager wordpress]$ docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
fxhh0c9onw2i        client              replicated          1/1                 busybox:latest      
nsk6nxis00y2        db                  replicated          1/1                 mysql:5.7           
[vagrant@swarm-manager wordpress]$ docker service ps db
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE            ERROR               PORTS
fn83ntbf4587        db.1                mysql:5.7           swarm-worker1       Running             Running 59 seconds ago

验证db容器（swarm-worker1 db容器创建在了swarm-worker1 node） ```sh [vagrant@swarm-worker1 ~]$ docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 03e7d7bca776 mysql:5.7 “docker-entrypoint.s…” 2 minutes ago Up 2 minutes 3306/tcp, 33060/tcp db.1.fn83ntbf45873q7vwr4bzov7h [vagrant@swarm-worker1 ~]$ docker exex -it 03e7 sh

cat /run/secrets/my-pw
admin123

mysql -u root -p
Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 5 Server version: 5.7.28 MySQL Community Server (GPL)

Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners.

Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the current input statement.

mysql>


- docker stack 使用 secret<br />
<br />更改之前的dockerfile
```yaml
version: '3'

services:

  web:
    image: wordpress
    ports:
      - 8080:80
    secrets:
      - my-pw #指定secret
    environment:
      WORDPRESS_DB_HOST: mysql
      WORDPRESS_DB_PASSWORD_FILE: /run/secrets/my-pw
    networks:
      - my-network
    depends_on:
      - mysql
    deploy:
      mode: replicated
      replicas: 3
      restart_policy:
        condition: on-failure
        delay: 5s
        max_attempts: 3
      update_config:
        parallelism: 1
        delay: 10s

  mysql:
    image: mysql
    secrets:
      - my-pw
    environment:
      MYSQL_ROOT_PASSWORD_FILE: /run/secrets/my-pw
      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

# secrets:
#   my-pw:
#    file: ./password 创建secret不推荐，推荐事先创建好

其余操作相同

9. Service更新

创建overlay网络（swarm-manager node）

[vagrant@swarm-manager wordpress]$ dcoker network create -d voerlay demo
[vagrant@swarm-manager wordpress]$ docker network ls
NETWORK ID          NAME                DRIVER              SCOPE
fbbe012e1221        bridge              bridge              local
jd53h59af2rj        demo                overlay             swarm
594d137fcf21        docker_gwbridge     bridge              local
1df5f5c0357a        host                host                local
m0nxe0fd0k7p        ingress             overlay             swarm
8b8926c5e805        none                null                local

创建容器（swarm-manager node）

[vagrant@swarm-manager wordpress]$ docker service create --name web --publish 8080:5000 --network demo xiaopeng163/python-flask-demo:1.0
[vagrant@swarm-manager wordpress]$ docker service ps web
ID                  NAME                IMAGE                               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
c47a9kwyh9gs        web.1               xiaopeng163/python-flask-demo:1.0   swarm-worker2       Running             Running about a minute ago

更新容器

首先横向扩展容器（swarm-manager node）

[vagrant@swarm-manager wordpress]$ docker service scale web=2
[vagrant@swarm-manager wordpress]$ docker service ps web
ID                  NAME                IMAGE                               NODE                DESIRED STATE       CURRENT STATE             ERROR               PORTS
c47a9kwyh9gs        web.1               xiaopeng163/python-flask-demo:1.0   swarm-worker2       Running             Running 7 minutes ago                         
ryfpv427p97m        web.2               xiaopeng163/python-flask-demo:1.0   swarm-manager       Running             Preparing 4 minutes ago

更新两个容器的镜像

[vagrant@swarm-manager wordpress]$ docker service update --image xiaopeng163/python-flask-demo:2.0 web
web
overall progress: 2 out of 2 tasks 
1/2: running   [==================================================>] 
2/2: running   [==================================================>] 
verify: Service converged 
[vagrant@swarm-manager wordpress]$ docker service ps web
ID                  NAME                IMAGE                               NODE                DESIRED STATE       CURRENT STATE            ERROR               PORTS
88ifmz2u04kb        web.1               xiaopeng163/python-flask-demo:2.0   swarm-worker2       Running             Running 2 minutes ago                        
c47a9kwyh9gs         \_ web.1           xiaopeng163/python-flask-demo:1.0   swarm-worker2       Shutdown            Shutdown 2 minutes ago                       
y5476lu7hvgz        web.2               xiaopeng163/python-flask-demo:2.0   swarm-manager       Running             Running 2 minutes ago                        
ryfpv427p97m         \_ web.2           xiaopeng163/python-flask-demo:1.0   swarm-manager       Shutdown            Shutdown 2 minutes ago

docker service update --help 查看更新命令更新两个容器时会一个一个更新不会让服务中断。

更新容器的端口

[vagrant@swarm-manager wordpress]$ docker service update --publish-rm 8080:5000 --publish-add 8088:5000 web
web
overall progress: 2 out of 2 tasks 
1/2: running   [==================================================>] 
2/2: running   [==================================================>] 
verify: Service converged 
[vagrant@swarm-manager wordpress]$ docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE                               PORTS                           
kmziylwlje61        web                 replicated          2/2                 xiaopeng163/python-flask-demo:2.0   *:8088->5000/tcp

Docker Stack的更新修改yml文件再次执行 docker stack deploy wordpress -c=docker-compose.yml 即可

1. Docker Swarm介绍

Docker Swarm两种角色Manager与Worker

Docker Swarm两种概念Service和Replicas

2. 安装

3. 创建一个三节点的swarm集群

使用Vagrantfile创建

进入三台虚拟主机

三台虚拟主机初始化docker swarm

4. Service的创建维护和水平扩展

创建Service

Service水平扩展

删除Service

5. swarm集群里通过service部署wordpress

创建网络

创建service容器

6. 集群服务间通信之Routing mesh

Routing Mesh的两种体现

Internal

Ingress

7. Docker Stack部署Wordpress

docker-compose.yml文件

定义一个stack

访问测试

删除stack

8. Docker Secret管理和使用

什么是Secret

Secret Management

创建Secret

使用secret

cat /run/secrets/my-pw

mysql -u root -p

9. Service更新

创建overlay网络（swarm-manager node）

创建容器（swarm-manager node）

更新容器

`Internal`

`Ingress`