end0tknr's kipple - web写経開発

太宰府天満宮の狛犬って、妙にカワイイ

Docker Swarm 、 Service 、Stack

以下の書籍「Docker/Kubernetes 実践コンテナ」にある

  • 3.5.1 Docker Swarm
  • 3.5.2 Service
  • 3.5.3 Stack
  • 3.5.4 ServiceをSwarm外から利用する

の写経。が、本日時点では、自分の理解が怪しい

www.amazon.co.jp

目次

Docker Swarm

┌─Docker───────────────────┐
│┌Registry  ─────┐        ┌Manager ──┤
││                    │port: ┏┥docker in d │      
││                    ┝━━━┫└──────┤
││┌Dir ───────┤ 5000 ┃┌Worker1～3─┤
│││/var/lib/registry │      ┗┥docker in d │
└┴┴──┰──────┴────┴──────┘
          ┃volume mount
┌─┬Dir ┸──────┬───────────┐
│  │registry-data     │                      │
│  └─────────┘                      │
└─Host────────────────────┘

$ vi docker-compose.yml

version: "3"
services:
  registry:
    container_name: registry
    image: registry:2.6
    ports:
      - 5000:5000
    volumes:
      - "./registry-data:/var/lib/registry"
  manager:
    container_name: manager
    image: docker:20.10.23-dind
    # hostの全deviceに接続okになるらしいが、詳細は理解:未
    privileged: true
    # cf. https://zenn.dev/hohner/articles/43a0da20181d34
    tty: true
    ports:
      - 8000:80
      - 9000:9000
    depends_on:
      - registry
    # hostには公開されない、container側のport
    expose:
      - 3375
    # 以下は https以外のhttp:5000で アクセスOKにする為
    command: "--insecure-registry registry:5000"
    volumes:
      - "./stack:/stack"
  worker01:
    container_name: worker01
    image: docker:20.10.23-dind
    privileged: true
    tty: true
    depends_on:
      - manager
      - registry
    expose:
      - 7946
      - 7946/udp
      - 4789/udp
    command: "--insecure-registry registry:5000"
  worker02:
    container_name: worker02
    image: docker:20.10.23-dind
    privileged: true
    tty: true
    depends_on:
      - manager
      - registry
    expose:
      - 7946
      - 7946/udp
      - 4789/udp
    command: "--insecure-registry registry:5000"

docker compose 起動と、起動していることの確認

$ docker compose up -d

$ docker container ls
CONTAINER ID  PORTS                                                     NAMES
3247a5969ab6  2375-2376/tcp,4789/udp,7946/tcp,7946/udp                  worker02
0aecc7a262b6  2375-2376/tcp,4789/udp,7946/tcp,7946/udp                  worker03
9a8f932cc2f9  2375-2376/tcp,4789/udp,7946/tcp,7946/udp                  worker01
cd870561d281  2375-2376/tcp,3375/tcp,:::9000->9000/tcp,:::8000->80/tcp  manager
32d8ae5003e2  :::5000->5000/tcp                                         registry

managerコンテナをswarnのマネージャに設定

$ docker container exec -it manager docker swarm init

Swarm initialized: current node (u6xgdpg665085m0qf64cnct0u) is now a manager.
To add a worker to this swarm, run the following command:
  docker swarm join --token \
    SWMTKN-1-4byqlau1bcz52zaj9jpmigudblrk3d482v8arwfd4syvywsfbo-50ow5mvipbyfagm4m8uken59k 172.18.0.3:2377
To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions.

worker01～03をswarnのノードに設定

$ docker container exec -it worker01 docker swarm join --token \
    SWMTKN-1-4byqlau1bcz52zaj9jpmigudblrk3d482v8arwfd4syvywsfbo-50ow5mvipbyfagm4m8uken59k \
    manager:2377
$ docker container exec -it worker02 docker swarm join --token \
    SWMTKN-1-4byqlau1bcz52zaj9jpmigudblrk3d482v8arwfd4syvywsfbo-50ow5mvipbyfagm4m8uken59k \
    manager:2377
$ docker container exec -it worker03 docker swarm join --token \
    SWMTKN-1-4byqlau1bcz52zaj9jpmigudblrk3d482v8arwfd4syvywsfbo-50ow5mvipbyfagm4m8uken59k \
    manager:2377

swarnノードの確認

$ docker container exec -it manager docker node ls
ID                            HOSTNAME       STATUS   MANAGER STATUS
u6xgdpg665085m0qf64cnct0u *   98e4c5b93225   Ready    Leader        
ssgz4ker8lvrfbpj3mtctjtsh     120608a59677   Ready                  
q5nuauip96qcgdctl4fmdj4j9     d4dc2bd958ec   Ready                  
lt3r8tnj48riejbozf7itsq1l     e54446b93f5e   Ready

dockerレジストリへ、イメージをpush

https://end0tknr.hateblo.jp/entry/20230125/1674635932

以前、上記のentryで作成した Dockerfile と main.go のイメージをタグ付けし、 Registry(port:5000)へ push

$ docker image tag example/echo:latest localhost:5000/example/echo:latest
$ docker image push localhost:5000/example/echo:latest

worker01で、先程、登録したイメージをpull

$ docker container exec -it worker01 docker image pull registry:5000/example/echo:latest

$ docker container exec -it worker01 docker image ls
REPOSITORY                   TAG       IMAGE ID       CREATED        SIZE
registry:5000/example/echo   latest    2cc31d7badf8   45 hours ago   803MB

Serviceの作成

$ docker container exec -it manager \
  docker service create --replicas 1 --publish 8000:8080 --name echo \
  registry:5000/example/echo:latest

$ docker container exec -it manager docker service ls
ID             NAME      MODE         REPLICAS   IMAGE                               PORTS
se9z57opyzi9   echo      replicated   1/1        registry:5000/example/echo:latest   *:8000->8080/tcp

6コのcontainerで分散実行

$ docker container exec -it manager docker service scale echo=6

$ docker container exec -it manager docker service ps echo | grep Running
echo.1    registry:5000/example/echo:latest   Running 15 minutes ago             
echo.2    registry:5000/example/echo:latest   Running  3 minutes ago              
echo.3    registry:5000/example/echo:latest   Running  3 minutes ago              
echo.4    registry:5000/example/echo:latest   Running  2 minutes ago              
echo.5    registry:5000/example/echo:latest   Running  2 minutes ago              
echo.6    registry:5000/example/echo:latest   Running  2 minutes ago

serviceを削除する場合、rm

$ docker container exec -it manager docker service rm echo
$ docker container exec -it manager docker service ls

Docker Stack

1コのイメージのみを扱うServiceに対し、Stackは複数Serviceをグルーピング

ch03という名称のoverlayネットワーク作成

$ docker container exec -it manager docker network create \
    --driver=overlay --attachable ch03

$ vi ./stack/ch03-webapi.yml

version: "3"
services:
  nginx:
    image: gihyodocker/nginx-proxy:latest
    deploy:
      replicas: 3
      placement:
        constraints: [node.role != manager]
    environment:
      SERVICE_PORTS: 80
      BACKEND_HOST: echo_api:8080
    depends_on:
      - api
    networks:
      - ch03
  api:
    image: registry:5000/example/echo:latest
    deploy:
      replicas: 3
      placement:
        constraints: [node.role != manager]
    networks:
      - ch03
networks:
  ch03:
    external: true

stackの配備

「echo」というstack名称で、deploy

$ docker container exec -it manager docker stack deploy \
  -c ./stack/ch03-webapi.yml echo

stack配備結果の確認

docker container exec -it manager docker stack ps echo

$ docker container exec -it manager docker stack services echo
NAME         MODE         REPLICAS   IMAGE                            
echo_api     replicated   3/3        registry:5000/example/echo:latest   
echo_nginx   replicated   3/3        gihyodocker/nginx-proxy:latest   

$ docker container exec -it manager docker stack ps echo
NAME           IMAGE                               NODE           CURRENT STATE
echo_api.1     registry:5000/example/echo:latest   e54446b93f5e   Running 4 minutes ago
echo_api.2     registry:5000/example/echo:latest   120608a59677   Running 4 minutes ago
echo_api.3     registry:5000/example/echo:latest   d4dc2bd958ec   Running 4 minutes ago
echo_nginx.1   gihyodocker/nginx-proxy:latest      e54446b93f5e   Running 4 minutes ago
echo_nginx.2   gihyodocker/nginx-proxy:latest      120608a59677   Running 4 minutes ago
echo_nginx.3   gihyodocker/nginx-proxy:latest      d4dc2bd958ec   Running 4 minutes ago

visualizerによる stack配備結果の確認

vi ./stack/visualizer.yml

version: "3"

services:
  app:
    image: dockersamples/visualizer
    ports:
      - "9000:8080"
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
    deploy:
      mode: global
      placement:
        constraints: [node.role == manager]

visualizerによる stack配備結果の確認

$ docker container exec -it manager docker stack deploy \
    -c ./stack/visualizer.yml \
    visualizer

上記を実行後、ブラウザで、http://192.168.56.113:9000/ へ アクセスすると、以下が表示されます。

stackの削除

$ docker container exec -it manager docker stack rm echo

HAProxyによるswarmクラスタ外からのservice利用

vi ./stack/ch03-ingress.yml

version: "3"

services:
  haproxy:
    image: dockercloud/haproxy
    networks: 
      - ch03 
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
    deploy:
      mode: global
      placement:
        constraints:
          - node.role == manager
    ports:
      - 80:80
      - 1936:1936 # for stats page (basic auth. stats:stats)

networks:
  ch03:
    external: true

配備

$ docker container exec -it manager docker stack deploy \
  -c /stack/ch03-webapi.yml echo

$ docker container exec -it manager docker stack deploy \
  -c /stack/ch03-ingress.yml ingress

$ docker container exec -it manager docker service ls
NAME            MODE       REPLICAS IMAGE                             PORTS
echo            replicated 6/6      registry:5000/example/echo:latest *:8000->8080/tcp
echo_api        replicated 3/3      registry:5000/example/echo:latest 
echo_nginx      replicated 3/3      gihyodocker/nginx-proxy:latest    
ingress_haproxy global     1/1      dockercloud/haproxy:latest        *:80->80/tcp, *:1936->1936/tcp
visualizer_app  global     1/1      dockersamples/visualizer:latest   *:9000->8080/tcp

$ curl http://localhost:8000/
Hello Docker!!