实战案例丨用 Docker Compose 快速运行一个 3 节点 Elasticsearch 集群 ...

出品丨Docker公司（ID：docker-cn）
编译丨小东
每周一、三、五，与您不见不散！

使用 Docker 在笔记本电脑上安装 Elasticsearch 集群进行测试是非常方便的。在这篇文章中，我将向您展示如何快速、简便地在 docker 上运行一个3节点的 elasticsearch 集群进行测试。

先决条件

我们需要设置“vm.max_map_count”内核参数：

$ sudo sysctl -w vm.max_map_count=262144

若要永久设置此值，请将其添加到“/etc/sysctl.conf”并使用“sudo sysctl -p”命令重新加载。

Docker Compose

我们将引用的 docker compose 文件：

version: '2.2'
services:
 elasticsearch:
   image: docker.elastic.co/elasticsearch/elasticsearch:6.2.4
   container_name: elasticsearch
   environment:
     - cluster.name=docker-cluster
     - bootstrap.memory_lock=true
     - http.cors.enabled=true
     - http.cors.allow-origin=*
     - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
   ulimits:
     memlock:
       soft: -1
       hard: -1
   volumes:
     - esdata1:/home/ruan/workspace/docker/elasticsearch/data
   ports:
     - 9200:9200
   networks:
     - esnet
 elasticsearch2:
   image: docker.elastic.co/elasticsearch/elasticsearch:6.2.4
   container_name: elasticsearch2
   environment:
     - cluster.name=docker-cluster
     - bootstrap.memory_lock=true
     - http.cors.enabled=true
     - http.cors.allow-origin=*
     - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
     - "discovery.zen.ping.unicast.hosts=elasticsearch"
   ulimits:
     memlock:
       soft: -1
       hard: -1
   volumes:
     - esdata2:/home/ruan/workspace/docker/elasticsearch/data
   networks:
     - esnet
 elasticsearch3:
   image: docker.elastic.co/elasticsearch/elasticsearch:6.2.4
   container_name: elasticsearch3
   environment:
     - cluster.name=docker-cluster
     - bootstrap.memory_lock=true
     - http.cors.enabled=true
     - http.cors.allow-origin=*
     - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
     - "discovery.zen.ping.unicast.hosts=elasticsearch"
   ulimits:
     memlock:
       soft: -1
       hard: -1
   volumes:
     - esdata3:/home/ruan/workspace/docker/elasticsearch/data
   networks:
     - esnet
 
 kibana:
   image: 'docker.elastic.co/kibana/kibana:6.3.2'
   container_name: kibana
   environment:
     SERVER_NAME: kibana.local
     ELASTICSEARCH_URL: http://elasticsearch:9200
   ports:
     - '5601:5601'
   networks:
     - esnet
 
 headPlugin:
   image: 'mobz/elasticsearch-head:5'
   container_name: head
   ports:
     - '9100:9100'
   networks:
     - esnet
 
volumes:
 esdata1:
   driver: local
 esdata2:
   driver: local
 esdata3:
   driver: local
 
networks:
 esnet:

现在，只需确保我们在 compose 文件中所引用的路径是真实存在的，在我展示的实例中，其路径是“/home/ruan/workspace/docker/elasticsearch/data”。

部署

使用 docker compose 来部署 elasticsearch 集群：

$ docker-compose up

它将在前台运行，您可以在控制台看到其输出结果。

测试 Elasticsearch

接下来，让我们运行几个查询。首先，检查群集运行状况 api：

$ curl http://127.0.0.1:9200/_cluster/health?pretty
{
 "cluster_name" : "docker-cluster",
 "status" : "green",
 "timed_out" : false,
 "number_of_nodes" : 3,
 "number_of_data_nodes" : 3,
 "active_primary_shards" : 1,
 "active_shards" : 2,
 "relocating_shards" : 0,
 "initializing_shards" : 0,
 "unassigned_shards" : 0,
 "delayed_unassigned_shards" : 0,
 "number_of_pending_tasks" : 0,
 "number_of_in_flight_fetch" : 0,
 "task_max_waiting_in_queue_millis" : 0,
 "active_shards_percent_as_number" : 100.0
}

创建一个复制计数为2的索引：

$ curl -H "Content-Type: application/json" -XPUT http://127.0.0.1:9200/test -d '{"number_of_replicas": 2}'

将文档提取到 elasticsearch：

$ curl -H "Content-Type: application/json" -XPUT http://127.0.0.1:9200/test/docs/1 -d '{"name": "ruan"}'
{"_index":"test","_type":"docs","_id":"1","_version":1,"result":"created","_shards":{"total":3,"successful":3,"failed":0},"_seq_no":0,"_primary_term":1}

查看索引：

$ curl http://127.0.0.1:9200/_cat/indices?v
health status index                      uuid                  pri rep docs.count docs.deleted store.size pri.store.size
green open  test                       w4p2Q3fTR4uMSYBfpNVPqw  5  2         1           0     3.3kb         1.1kb
green open  .monitoring-es-6-2018.04.29 W69lql-rSbORVfHZrj4vug  1  1      1601          38       4mb           2mb

Kibana

Kibana 也包含在应用栈中，可以通过“http://localhost:5601/”访问它，如下图所示：

Elasticsearch Head UI

我喜欢直接使用 RESTFul API，但是如果您想使用 UI 与 Elasticsearch 进行交互，你可以通过“http：// localhost：9100/”访问它，如下图所示：

删除群集

因为它在前台运行，所以您只需按下“ctrl + c”就可以持续地将数据保存在我们的 compose 文件中。当您再次启动集群时，数据仍然会存在。

浏览 https://www.elastic.co/guide/en/elasticsearch/reference/current/docker.html 了解更多Elasticsearch 的相关信息！