docker swarm 部署ES集群

0. 环境准备

修改系统配置，在所有主机中，编辑 /etc/sysctl.conf，追加以下内容：

vm.max_map_count=262144

保存后，执行sysctl -p

1. docker-compose文件准备

docker-compose-es-cluster.yml

version: '3.3'
services:
  kibana:
    image: docker.elastic.co/kibana/kibana:7.6.2
    environment:
      - ELASTICSEARCH_URL=http://es_master:9200
      - ELASTICSEARCH_HOSTS=http://es_master:9200
      - ELASTICSEARCH_USERNAME=elastic
      - ELASTICSEARCH_PASSWORD=vsUZGKNvjWRtTKPmDG
    ports:
      - 5601:5601
    networks:
      - elastic
    deploy:
      mode: replicated
      replicas: 1
      resources:
        limits:
          memory: 800M
      placement:
        constraints:
          - node.role==manager
  es_master:
    image: docker.elastic.co/elasticsearch/elasticsearch:7.17.8
    environment:
      - node.name=es_master
      - cluster.name=es-docker-cluster
      - discovery.seed_hosts=es_node
      - cluster.initial_master_nodes=es_master,es_node
      - network.host=0
      - network.publish_host=_eth0_
      - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
      - path.repo=/usr/share/elasticsearch/backups
      - xpack.security.enabled=true
      - xpack.security.audit.enabled=false
      - xpack.security.transport.ssl.enabled=false
      - ELASTIC_PASSWORD=vsUZGKNvjWRtTKPmDG
    volumes:
      - es_master_data:/usr/share/elasticsearch/data
      - es_master_logs:/usr/share/elasticsearch/logs
    ports:
      - 9200:9200
      - 9300:9300
    networks:
      - elastic
    deploy:
      mode: replicated
      replicas: 1
      resources:
        limits: # es_maseter 资源使用上限
          cpus: "0.50"
          memory: 1G
        reservations: # es_maseter 随时可以使用的资源
          cpus: "0.25"
          memory: 1G
      placement:
        constraints:
          - node.role==manager # 部署位置
  es_node:
    image: docker.elastic.co/elasticsearch/elasticsearch:7.17.8
    environment:
      - node.name=es_node
      - cluster.name=es-docker-cluster
      - discovery.seed_hosts=es_master
      - cluster.initial_master_nodes=es_node,es_master
      - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
      - path.repo=/usr/share/elasticsearch/backups
      - xpack.security.enabled=true
      - ELASTIC_PASSWORD=vsUZGKNvjWRtTKPmDG
    volumes:
      - es_node_data:/usr/share/elasticsearch/data
      - es_node_logs:/usr/share/elasticsearch/logs
    networks:
      - elastic
    deploy:
      mode: replicated
      replicas: 2
      resources:
        limits:
          cpus: "0.50"
          memory: 1G
        reservations:
          cpus: "0.25"
          memory: 1G
      placement:
        constraints:
          - node.role==manager

volumes:
  es_master_data:
    driver: local
  es_master_logs:
    driver: local
  es_node_data:
    driver: local
  es_node_logs:
    driver: local

networks:
  elastic:
    driver: overlay # 必须使用swarm类型的网络

2. 部署服务

部署服务使用 docker stack deploy，其中 -c 参数指定 compose 文件名。

$ docker stack deploy -c docker-compose-es-cluster.yml es

验证ES服务：打开浏览器输入 任一节点IP:9200 即可看到各节点运行状态。如下图所示：

此时ES已成功启动，但是还需要验证集群是否搭建成功。

验证集群：打开浏览器输入 任一节点IP:9200/_cluster/health 即可看到集群状态。如下图所示：

验证Kibana：打开浏览器输入 任一节点IP:5601 能看到kibana的登录页则表示成功。

3. 查看服务

$ docker service ls
ID             NAME           MODE         REPLICAS   IMAGE                                                  PORTS
ou62f7ff0ast   es_es_master   replicated   1/1        docker.elastic.co/elasticsearch/elasticsearch:7.17.8   *:9200->9200/tcp, *:9300->9300/tcp
6pyqh40a2jox   es_es_node     replicated   2/2        docker.elastic.co/elasticsearch/elasticsearch:7.17.8   
kpc66kphr4mb   es_kibana      replicated   1/1        docker.elastic.co/kibana/kibana:7.6.2                  *:5601->5601/tcp

4. 常见问题解决

1. 找不到master节点

报错信息摘要：master not discovered yet, this node has not previously joined a bootstrapped (v7+) cluster, and this node must discover master-eligible nodes ...

解决方案：这种情况一般可以在服务down掉之后，删除相关的volume，然后重新部署。但是生产环境慎用down操作。服务启动之后如果需要重启可以通过重新执行docker stack deploy -c docker-compose-es-cluster.yml es来使得配置生效。