ElasticSearch 5學習(3)——單台服務器部署多個節點

一般情況下單台服務器只會部署一個ElasticSearch node，但是在學習過程中，很多情況下會需要實現ElasticSearch的分布式效果，所以需要啟動多個節點，但是學習開發環境（不想開多個虛擬機實現多個服務器的效果），所以就想着在一台服務器上部署多個結點（下文以2個結點作為例子），兩個節點分別稱為實例一、二。

1、首先將elasticsearch-5.0.2文件夾再復制一份

# wuxiwei @ wuxiwei in ~/software
$ cp -R elasticsearch-5.0.2 elasticsearch-5.0.2-node-2
# wuxiwei @ wuxiwei in ~/software
$ ls -l
total 145568
drwxr-xr-x  12 wuxiwei  staff       408 12 11 16:23 elasticsearch-5.0.2
drwxr-xr-x  12 wuxiwei  staff       408 12 11 16:27 elasticsearch-5.0.2-node-2

2、主要工作就是修改elasticsearch.yml配置文件。

實例二：config目錄下的elasticsearch.yml內容

將node.name: node-1 修改為 node-2，

3、分別開啟兩個節點

# wuxiwei @ wuxiwei in ~/software/elasticsearch-5.0.2
$ ./bin/elasticsearch

# wuxiwei @ wuxiwei in ~/software/elasticsearch-5.0.2
$ cd ../elasticsearch-5.0.2-node-2
# wuxiwei @ wuxiwei in ~/software/elasticsearch-5.0.2-node-2
$ ./bin/elasticsearch

4、查詢是否成功

$ curl -i -XGET 'http://localhost:9200/_cluster/health?pretty'\;
HTTP/1.1 200 OK
content-type: application/json; charset=UTF-8
content-length: 457

{
  "cluster_name" : "my",
  "status" : "green",
  "timed_out" : false,
  "number_of_nodes" : 2,
  "number_of_data_nodes" : 2,
  "active_primary_shards" : 20,
  "active_shards" : 40,
  "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
}

也可以通過Kibana查看節點效果

踩過的坑

（1）如果修改了配置文件的 http.port、transport.tcp.port項，一定要將各個節點的值設置不同，否則會出現占用的情況。正常如果不修改，默認會分配值。

（2）示例二開啟時，實例一報警告（實際操作中可以忽略，不然將無法實現ES的分布式集群作用）：

[2016-12-11T18:06:43,678][WARN ][o.e.d.z.ElectMasterService] [node-1] value for setting "discovery.zen.minimum_master_nodes" is too low. This can result in data loss! Please set it to at least a quorum of master-eligible nodes (current value: [-1], total number of master-eligible nodes used for publishing in this round: [2])

是因為默認情況下 discovery.zen.minimum_master_nodes=1 一台服務器只能有一個主節點，所以在實例二的配置文件中可以添加 node.master: false。

（3）示例二不能開啟，報如下錯誤：

[2016-12-11T16:53:02,711][INFO ][o.e.d.z.ZenDiscovery     ] [node-2] failed to send join request to master [{node-1}{vP19PMOyT2ilJKRAqgn78w}{jDULCExERXGHp4VXpbyuJA}{127.0.0.1}{127.0.0.1:9300}], reason [RemoteTransportException[[node-1][127.0.0.1:9300][internal:discovery/zen/join]]; nested: IllegalArgumentException[can't add node {node-2}{vP19PMOyT2ilJKRAqgn78w}{qhDDVzwZQ0GXZXhIMmpGKA}{127.0.0.1}{127.0.0.1:9301}, found existing node {node-1}{vP19PMOyT2ilJKRAqgn78w}{jDULCExERXGHp4VXpbyuJA}{127.0.0.1}{127.0.0.1:9300} with the same id but is a different node instance]; ]
[2016-12-11T16:53:02,911][INFO ][o.e.x.m.e.Exporters      ] [node-2] skipping exporter [default_local] as it isn't ready yet
[2016-12-11T16:53:02,912][ERROR][o.e.x.m.AgentService     ] [node-2] exception when exporting documents
org.elasticsearch.xpack.monitoring.exporter.ExportException: exporters are either not ready or faulty
	at org.elasticsearch.xpack.monitoring.exporter.Exporters.export(Exporters.java:188) ~[x-pack-5.0.2.jar:5.0.2]
	at org.elasticsearch.xpack.monitoring.AgentService$ExportingWorker.run(AgentService.java:208) [x-pack-5.0.2.jar:5.0.2]
	at java.lang.Thread.run(Thread.java:745) [?:1.8.0_111]

是因為復制的elasticsearch文件夾下包含了data文件中示例一的節點數據，需要把示例二data文件下的文件清空。

轉載請注明出處。
作者：wuxiwei
出處：http://www.cnblogs.com/wxw16/p/6160186.html