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企业运维容器之 docker 三剑客swarm

2021/6/3 17:02:11   来源:

企业运维容器之 docker 三剑客swarm

    • 1. Docker Swarm简介
    • 2. Docker Swarm实践
    • 3. docker stack部署
    • 4. Portainer可视化

1. Docker Swarm简介

  • Swarm 在 Docker 1.12 版本之前属于一个独立的项目,在 Docker 1.12 版本发布之后,该项目合并到了 Docker 中,成为 Docker 的一个子命令。
  • Swarm 是 Docker 社区提供的唯一一个原生支持 Docker 集群管理的工具。
  • Swarm可以把多个 Docker 主机组成的系统转换为单一的虚拟 Docker 主机,使得容器可以组成跨主机的子网网络。
  • Docker Swarm 是一个为 IT 运维团队提供集群和调度能力的编排工具
  • Docker Swarm 优点
    任何规模都有高性能表现,灵活的容器调度,服务的持续可用性和 Docker API 及整合支持的兼容性。
    Docker Swarm 为 Docker 化应用的核心功能(诸如多主机网络和存储卷管理)提供原生支持。
  • docker swarm 相关概念
    节点分为管理 (manager) 节点和工作 (worker) 节点;
    任务 (Task)是 Swarm 中的最小的调度单位,目前来说就是一个单一的容器。
    服务 (Services) 是指一组任务的集合,服务定义了任务的属性。

在这里插入图片描述

2. Docker Swarm实践

  • 创建 Swarm 集群
    初始化集群: docker swarm init
[root@server1 ~]# docker swarm init
Swarm initialized: current node (lwl1574190s7dk2m0vwq8fo4u) is now a manager.

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

    docker swarm join --token SWMTKN-1-6042qvxj27capknpxotehy0zk380r6dg0pgu5qv7g0z04slv6x-bh8eio618l0tu2pfnkm65emwd 172.25.15.1:2377

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

该指令只能在 leader 上执行

[root@server1 ~]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
lwl1574190s7dk2m0vwq8fo4u *   server1             Ready               Active              Leader              19.03.15

根据提示在其他docker节点上执行命令,其他结点加入:

[root@server2 compose]# docker swarm join --token SWMTKN-1-6042qvxj27capknpxotehy0zk380r6dg0pgu5qv7g0z04slv6x-bh8eio618l0tu2pfnkm65emwd 172.25.15.1:2377
This node joined a swarm as a worker.


[root@server3 docker]# docker swarm join --token SWMTKN-1-6042qvxj27capknpxotehy0zk380r6dg0pgu5qv7g0z04slv6x-bh8eio618l0tu2pfnkm65emwd 172.25.15.1:2377
This node joined a swarm as a worker.

此时再次查看其结点信息:

[root@server1 ~]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
lwl1574190s7dk2m0vwq8fo4u *   server1             Ready               Active              Leader              19.03.15
[root@server1 ~]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
lwl1574190s7dk2m0vwq8fo4u *   server1             Ready               Active              Leader              19.03.15
zhhp5501wu76cluglinzdv70w     server2             Ready               Active                                  19.03.15
k39m95d6c0oc40biyzb5cdyix     server3             Ready               Active                                  19.03.15

会自动创建一个网络:

[root@server1 ~]# docker network ls
NETWORK ID          NAME                        DRIVER              SCOPE
e3c1f4d37c07        bridge                      bridge              local
8535c5281d20        docker_gwbridge             bridge              local
8a1d46231c4e        harbor_harbor               bridge              local
9060ca2c0d1e        harbor_harbor-chartmuseum   bridge              local
7b739bd64a8f        harbor_harbor-clair         bridge              local
1d41c7aa2f92        harbor_harbor-notary        bridge              local
37f739e41113        harbor_notary-sig           bridge              local
9894c728c0a7        host                        host                local
zqor0s9qs2ih        ingress                     overlay             swarm
fcd1bdec9b88        none                        null                local

创建服务:docker service create --name mysrc --replicas 2 -p 80:80 nginx,表示创建一个服务,名称为 mysrc,副本数为 2 ,端口映射;具体的参数可以用命令来查看帮助: docker service create --help

命令解释:
docker service create 命令创建一个服务
–name 服务名称命名为 my_cluster
–network 指定服务使用的网络模型
–replicas 设置启动的示例数为3

以上在创建时,会非常慢,当没有镜像时会从网上拉取;
此处用 1 号主机来作为本地软件仓库所在的主机;将2号主机作为管理结点;其余3号和4号作为两个结点主机来观察实验效果;
在开一个虚拟机,在 234 上来观察实验效果,让1为本地软件仓库;
然后让1主结点下线,2上线;

首先新开一台4号主机,利用 docker-machine 来为其部署容器;

[root@server1 ~]# ssh-copy-id server4
[root@server1 ~]# docker-machine create -d generic --generic-ip-address 172.25.25.4 --engine-install-url "http://172.25.25.250/get-docker.sh" server4
[root@server1 ~]# docker-machine ls
NAME      ACTIVE   DRIVER    STATE     URL                      SWARM   DOCKER      ERRORS
server2   -        generic   Running   tcp://172.25.25.2:2376           v19.03.25   
server3   -        generic   Running   tcp://172.25.25.3:2376           v19.03.25   
server4   -        generic   Running   tcp://172.25.25.4:2376           v19.03.25   

写入解析,指定仓库:

[root@server4 ~]# vim /etc/hosts
[root@server4 ~]# cd /etc/docker/
[root@server4 docker]# ls
ca.pem  certs.d  daemon.json  key.json  server-key.pem  server.pem
[root@server4 docker]# systemctl reload docker.service 

[root@server3 docker]# vim /etc/hosts
[root@server3 docker]# ls
ca.pem  certs.d  daemon.json  key.json  server-key.pem  server.pem
[root@server3 docker]# systemctl reload docker.service 
[root@server3 docker]# docker info

让4号主机也加入swarm 集群:

[root@server4 docker]# docker swarm join --token SWMTKN-1-6042qvxj27capknpxotehy0zk380r6dg0pgu5qv7g0z04slv6x-bh8eio618l0tu2pfnkm65emwd 172.25.15.1:2377
This node joined a swarm as a worker.

[root@server1 ~]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
lwl1574190s7dk2m0vwq8fo4u *   server1             Ready               Active              Leader              19.03.15
zhhp5501wu76cluglinzdv70w     server2             Ready               Active                                  19.03.15
jxlltu5j93daz2k8mhj154gkc     server4             Ready               Active                                  19.03.15
k39m95d6c0oc40biyzb5cdyix     server4             Ready               Active                                  19.03.15

此时让原先控制结点下线,然后2号结点来接管:

[root@server1 ~]# docker node promote server2 	
	##先提升2号主机的身份
Node server2 promoted to a manager in the swarm.
[root@server1 ~]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
lwl1574190s7dk2m0vwq8fo4u *   server1             Ready               Active              Leader              19.03.15
zhhp5501wu76cluglinzdv70w     server2             Ready               Active              Reachable           19.03.15
jxlltu5j93daz2k8mhj154gkc     server4             Ready               Active                                  19.03.15
k39m95d6c0oc40biyzb5cdyix     server4             Ready               Active                                  19.03.15
[root@server1 ~]# docker node demote server1
Manager server1 demoted in the swarm.
	##降低1号主机的身份,降低身份之后2号主机会自动接管,此时在1号主机上便不可在查看结点信息
[root@server1 ~]# docker node ls
Error response from daemon: This node is not a swarm manager. Worker nodes can't be used to view or modify cluster state. Please run this command on a manager node or promote the current node to a manager.

当1号主机下线之后,原先准备的2号主机便会自动接管。此时只能从2号主机上查看结点信息;

[root@server2 docker]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
lwl1574190s7dk2m0vwq8fo4u     server1             Ready               Active                                  19.03.15
zhhp5501wu76cluglinzdv70w *   server2             Ready               Active              Leader              19.03.15
jxlltu5j93daz2k8mhj154gkc     server4             Ready               Active                                  19.03.15
k39m95d6c0oc40biyzb5cdyix     server4             Ready               Active                                  19.03.15

让1号主机离开 swarm 集群;

[root@server1 ~]# docker swarm leave 
Node left the swarm.

当1号主机离开集群之后,此时在管理主机上看到的信息是 down ,可以在管理主机上删除已经 down 的主机;

[root@server2 docker]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
lwl1574190s7dk2m0vwq8fo4u     server1             Down                Active                                  19.03.15
zhhp5501wu76cluglinzdv70w *   server2             Ready               Active              Leader              19.03.15
jxlltu5j93daz2k8mhj154gkc     server4             Ready               Active                                  19.03.15
k39m95d6c0oc40biyzb5cdyix     server4             Ready               Active                                  19.03.15

[root@server2 docker]# docker node rm server1 
server1
[root@server2 docker]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
zhhp5501wu76cluglinzdv70w *   server2             Ready               Active              Leader              19.03.15
jxlltu5j93daz2k8mhj154gkc     server4             Ready               Active                                  19.03.15
k39m95d6c0oc40biyzb5cdyix     server4             Ready               Active                                  19.03.15

开启仓库,开启之后在网页访问看是否信息完整;

[root@server1 harbor]# docker-compose start

让其他几个结点将仓库地址指向本地仓库;

[root@server3 ~]# cd /etc/docker/
[root@server3 docker]# ls
ca.pem  key.json  server-key.pem  server.pem
[root@server3 docker]# ls
ca.pem  certs.d  daemon.json  key.json  server-key.pem  server.pem
[root@server3 docker]# cat daemon.json 
{
	"registry-mirrors": ["https://reg.westos.org"]
}
[root@server3 docker]# docker info

此时再次创建服务 ,此时在创建时就很快;

[root@server2 docker]# docker service create --name mysrc --replicas 3 -p 80:80 nginx
g43i606dexdivzkizfezr2hws
overall progress: 3 out of 3 tasks 
1/3: running   
2/3: running   
3/3: running   
verify: Service converged 

[root@server2 docker]# docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
g43i606dexdi        mysrc               replicated          3/3                 nginx:latest        *:80->80/tcp

[root@server2 docker]# docker service ps mysrc 	
	##查看该服务三个容器分别运行在那些结点上
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
ym8aya7uzm1f        mysrc.1             nginx:latest        server2             Running             Running about a minute ago                       
kj8aa1rvvjgr        mysrc.2             nginx:latest        server4             Running             Running about a minute ago                       
6kaj088cdmfm        mysrc.3             nginx:latest        server4             Running             Running about a minute ago  

此时虽然可以访问,但是看到的信息都是测试页,效果不明显,此时再次上传一个镜像来做测试;

[root@server1 ~]# docker load -i myapp.tar 
d39d92664027: Loading layer  4.232MB/4.232MB
8460a579ab63: Loading layer  11.61MB/11.61MB
c1dc81a64903: Loading layer  3.584kB/3.584kB
68695a6cfd7d: Loading layer  4.608kB/4.608kB
05a9e65e2d53: Loading layer  16.38kB/16.38kB
a0d2c4392b06: Loading layer   7.68kB/7.68kB
Loaded image: ikubernetes/myapp:v1
Loaded image: ikubernetes/myapp:v2
[root@server1 ~]# docker images | grep myapp
ikubernetes/myapp                 v1                               d4a5e0eaa84f        3 years ago         15.5MB
ikubernetes/myapp                 v2                               54202d3f0f35        3 years ago         15.5MB
[root@server1 ~]# docker tag ikubernetes/myapp:v1 reg.westos.org/library/myapp:v1
[root@server1 ~]# docker tag ikubernetes/myapp:v2 reg.westos.org/library/myapp:v2
[root@server1 ~]# docker push reg.westos.org/library/myapp:v1 
The push refers to repository [reg.westos.org/library/myapp]
[root@server1 ~]# docker push reg.westos.org/library/myapp:v2
The push refers to repository [reg.westos.org/library/myapp]

此时再次创建服务,来测试:

[root@server2 docker]# docker service rm mysrc 
mysrc
[root@server2 docker]# docker service create --name mysrc --replicas 3 -p 80:80 myapp:v1
yibrpco1vuc1wziyl8vlskjjh
overall progress: 3 out of 3 tasks 
1/3: running   
2/3: running   
3/3: running   
verify: Service converged 

测试负载均衡,此时在访问任何一个都是负载均衡的;

[root@westos ~]# curl 172.25.25.2
Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a>
[root@westos ~]# curl 172.25.25.2/hostname.html
4fa916724b12
[root@westos ~]# curl 172.25.25.2/hostname.html
451e21d2a9cf
[root@westos ~]# curl 172.25.25.2/hostname.html
0d7e76ef89d2
[root@westos ~]# curl 172.25.25.2/hostname.html
4fa916724b12
[root@westos ~]# curl 172.25.25.2/hostname.html
451e21d2a9cf
[root@westos ~]# curl 172.25.25.2/hostname.html
0d7e76ef89d2
[root@westos ~]# curl 172.25.25.2/hostname.html
4fa916724b12

弹性拉伸:

[root@server2 docker]# docker service scale mysrc=6
mysrc scaled to 6
overall progress: 6 out of 6 tasks 
1/6: running   
2/6: running   
3/6: running   
4/6: running   
5/6: running   
6/6: running   
verify: Service converged 
[root@server2 docker]# docker service ps mysrc 
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
jwqv0y21uzj2        mysrc.1             myapp:v1            server2             Running             Running about a minute ago                       
1qcjndb06k8c        mysrc.2             myapp:v1            server4             Running             Running about a minute ago                       
v86koacmvnjn        mysrc.3             myapp:v1            server4             Running             Running about a minute ago                       
oum30ikxxv9g        mysrc.4             myapp:v1            server4             Running             Running 17 seconds ago                           
w2r1bksii1xq        mysrc.5             myapp:v1            server2             Running             Running 17 seconds ago                           
wvz17t7ao5lg        mysrc.6             myapp:v1            server4             Running             Running 17 seconds ago      

然后可以再次测试负载均衡的效果,新加入的会自动加入负载均衡队列。

为了更加可视化的观察实验效果,下载一个监控镜像进入可视化的图形界面来观察其效果;

[root@server1 ~]# docker load -i visualizer.tar 
[root@server1 ~]# docker images  | grep visualizer
dockersamples/visualizer          latest                           17e55a9b2354        3 years ago         148MB
[root@server1 ~]# docker tag dockersamples/visualizer reg.westos.org/library/visualizer:latest
[root@server1 ~]# docker push reg.westos.org/library/visualizer

部署 swarm 监控,再次创建服务来观察实验效果:

[root@server2 ~]# docker service create \
--name=viz --publish=8080:8080/tcp \
--constraint=node.role==manager \
--mount=type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock 
visualizer:latest

以上信息表示创建一个服务,名称为 viz 端口为 8080,限制其只能在管理结点,将本机服务挂载到容器中,最后为镜像名称。

创建完成之后,此时即可在网页上查看:

在这里插入图片描述
此时扩容为10个时,再次查看:

[root@server2 docker]# docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
reye7bjec995        mysrc               replicated          6/6                 myapp:v1            *:80->80/tcp
fvr1j0ck125p        viz                 replicated          1/1                 visualizer:latest   *:8080->8080/tcp
[root@server2 docker]# docker service scale mysrc=10
[root@server2 docker]# docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
reye7bjec995        mysrc               replicated          10/10               myapp:v1            *:80->80/tcp
fvr1j0ck125p        viz                 replicated          1/1                 visualizer:latest   *:8080->8080/tcp
[root@server2 docker]# docker service ps mysrc
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
a8iwy0qdhzbh        mysrc.1             myapp:v1            server3             Running             Running 17 minutes ago                           
uk3x8pcjoj9u        mysrc.2             myapp:v1            server2             Running             Running 17 minutes ago                           
tm2ojnskkk1v        mysrc.3             myapp:v1            server4             Running             Running 17 minutes ago                           
nsijhp2jlepu        mysrc.4             myapp:v1            server4             Running             Running 13 minutes ago                           
37cjrw61yrg1        mysrc.5             myapp:v1            server3             Running             Running 13 minutes ago                           
nhhvz5ngj8q1        mysrc.6             myapp:v1            server2             Running             Running 13 minutes ago                           
gqx6cp663fnd        mysrc.7             myapp:v1            server3             Running             Running about a minute ago                       
jjscxjnz8d66        mysrc.8             myapp:v1            server4             Running             Running about a minute ago                       
spsrme15yedm        mysrc.9             myapp:v1            server2             Running             Running about a minute ago                       
klyzs5qblfud        mysrc.10            myapp:v1            server3             Running             Running about a minute ago                       
[root@server2 docker]# docker service ps viz
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE           ERROR               PORTS
iljzp0c1xbkn        viz.1               visualizer:latest   server2             Running             Running 3 minutes ago      
  • 滚动更新
    docker service update --image httpd --update-parallelism 2 --update-delay 5s my_cluster 的参数可以用 docker service update --help 来查看;
    –image 指定要更新的镜像
    –update-parallelism 指定最大同步更新的任务数
    –update-delay 指定更新间隔
[root@server2 docker]# docker service update --image myapp:v2 --update-parallelism 2 --update-delay 2s mysrc

此时测试时可以看到其调度到 v2 上,可视化页面能清除的看到其变化;

[root@westos ~]# curl 172.25.25.2
Hello MyApp | Version: v2 | <a href="hostname.html">Pod Name</a>

在这里插入图片描述

3. docker stack部署

  • 基于 Docker Swarm 之上来完成应用的部署,面向大规模场景下的多服务部署和管理。
  • docker stack与docker-compose的区别:
    Docker stack不支持“build”指令,它是需要镜像是预先已经构建好的, 所以docker-compose更适合于开发场景;
    Docker Compose是一个Python项目,使用Docker API规范来操作容器。
    Docker Stack功能包含在Docker引擎中,是swarm mode的一部分。
    Docker stack不支持基于第2版写的docker-compose.yml ,也就是version版本至少为3。然而Docker Compose对版本为2和3的 文件仍然可以处理;
    docker stack把docker compose的所有工作都做完了,因此docker stack将占主导地位。
  • docker stack相关命令:

在这里插入图片描述

compose 来完成部署,创建文件,写入 yaml 文件;

先删除之前创建的服务;

[root@server2 docker]# docker service rm mysrc
mysrc
[root@server2 docker]# docker service rm viz
viz

然后编辑 yaml 文件;

[root@server2 ~]# mkdir compose
[root@server2 ~]# cd compose/
[root@server2 compose]# vim docker-compose.yaml
[root@server2 compose]# cat docker-compose.yaml 
version: "3.8"
services:

  mysvc:
    image: nginx:latest
    ports:
      - "80:80"
    deploy:
      resources:			##做资源限制
        limits:				##做cpu 上限限制
          cpus: '0.50'		
          memory: 200M		##做内存上限限制
        reservations:		##最少限制
          cpus: '0.25'
          memory: 50M
      replicas: 3			##副本数
      update_config:
        parallelism: 2		##每次更新两个
        delay: 5s			##延迟2s
      restart_policy:		##当容器故障时自动重启
        condition: on-failure

  visualizer:
    image: visualizer:latest
    ports:			##端口映射
      - "8080:8080"
    stop_grace_period: 1m30s
    volumes:		##挂载
      - "/var/run/docker.sock:/var/run/docker.sock"
    deploy:
      placement:
        constraints:
          - "node.role==manager"		##限制在管理结点

利用 yaml 文件来开始部署:

[root@server2 compose]# docker stack deploy -c docker-compose.yaml myservice
Creating network myservice_default
Creating service myservice_mysvc
Creating service myservice_visualizer

[root@server2 compose]# docker service ls
ID                  NAME                   MODE                REPLICAS            IMAGE               PORTS
ylf14u27qpa8        myservice_mysrc        replicated          3/3                 nginx:latest        *:80->80/tcp
zqww2cf6r7ij        myservice_visualizer   replicated          1/1                 visualizer:latest   *:8080->8080/tcp

[root@server2 compose]# docker service ps myservice_mysrc
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE           ERROR               PORTS
ir8qdahngvii        myservice_mysrc.1   nginx:latest        server2             Running             Running 2 minutes ago                       
rcjtmdkpr312        myservice_mysrc.2   nginx:latest        server4             Running             Running 2 minutes ago                       
li4wn2zn0ym4        myservice_mysrc.3   nginx:latest        server4             Running             Running 2 minutes ago                       
[root@server2 compose]# docker service ps myservice_visualizer
ID                  NAME                     IMAGE               NODE                DESIRED STATE       CURRENT STATE                ERROR               PORTS
pa2ksznaeahi        myservice_visualizer.1   visualizer:latest   server2             Running             Running about a minute ago 

在这里插入图片描述

4. Portainer可视化

集群最好有一个 web 接口,下载portainer 图形工具,配置本地镜像仓库;

为了区别于其他的镜像,此处在在 habor 上新建一个项目;

在这里插入图片描述
然后将镜像上传至仓库;供 server 端下载;

[root@server1 ~]# docker load -i portainer-agent.tar
[root@server1 ~]# docker load -i portainer.tar 
[root@server1 ~]# docker images | grep portainer
portainer/portainer                 latest                           19d07168491a        2 years ago         74.1MB
portainer/agent                     latest                           9335796fedf9        2 years ago         12.4MB
[root@server1 ~]# docker tag portainer/portainer:latest reg.westos.org/portainer/portainer:latest
[root@server1 ~]# docker tag portainer/agent:latest reg.westos.org/portainer/agent:latest
[root@server1 ~]# docker push reg.westos.org/portainer/portainer
[root@server1 ~]# docker push reg.westos.org/portainer/agent:latest 

在管理结点上编辑yaml语言;此处所有的服务端和 agent 共享一个网络;

[root@server2 ~]# ls
compose  haproxy.tar   portainer-agent-stack.yml
[root@server2 ~]# vim portainer-agent-stack.yml
version: '3.2'

services:
  agent:
    image: portainer/agent
    environment:
      # REQUIRED: Should be equal to the service name prefixed by "tasks." when
      # deployed inside an overlay network
      AGENT_CLUSTER_ADDR: tasks.agent
      # AGENT_PORT: 9001
      # LOG_LEVEL: debug
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - /var/lib/docker/volumes:/var/lib/docker/volumes
    networks:
      - agent_network
    deploy:
      mode: global
      placement:
        constraints: [node.platform.os == linux]

  portainer:
    image: portainer/portainer
    command: -H tcp://tasks.agent:9001 --tlsskipverify
    ports:
      - "9000:9000"
    volumes:
      - portainer_data:/data
    networks:
      - agent_network
    deploy:
      mode: replicated
      replicas: 1
      placement:
        constraints: [node.role == manager]

networks:
  agent_network:
    driver: overlay
    attachable: true

volumes:
  portainer_data:

开始部署:

[root@server2 ~]# docker stack deploy -c portainer-agent-stack.yml portainer
Creating network portainer_agent_network
Creating service portainer_portainer
Creating service portainer_agent
[root@server2 ~]# docker stack ls
NAME                SERVICES            ORCHESTRATOR
myservice           2                   Swarm
portainer           2                   Swarm

此时在网页中便可可以访问:http://172.25.25.2:9000,第一次登陆时强行更改秘密;

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然后可以通过图形化的界面来在线拉伸;

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