環境

centos7
elastichsearch-6.2.3
node v8.11.1

安裝elasticsearch

安裝elasticsearch請檢視：https://blog.csdn.net/mjlfto/article/details/79769152

安裝node

安裝elasticsearch-head外掛需要nodejs的支援，所以此處講解一下安裝nodejs步驟

1.到nodejs官網現在最新nodejs，官網下載地址：https://nodejs.org/en/download/ 

2. 解壓壓縮包 

3.在/etc/profile中配置好path環境變數 

4.執行node -v驗證安裝

[root@localhost elasticsearch-head]# node -v
v8.11.1
[root@localhost elasticsearch-head]# 

下載elastichsearch-head外掛

1.地址：https://github.com/mobz/elasticsearch-head 
2.安裝git :yum install git 
3.clone elasticsearch-head: git clone https://github.com/mobz/elasticsearch-head.git

安裝elastichsearch-head外掛

到elasticsearch-head目錄下， 執行npm install 命令， 執行該命名可能會出現以下錯誤：

[root@localhost elasticsearch-head]# npm install 

> phantomjs-prebuilt@2.1.16 install /home/a123/elasticsearch-6.2.3/plugins/elasticsearch-head/node_modules/phantomjs-prebuilt
> node install.js

sh: node: command not found
npm WARN elasticsearch-head@0.0.0 license should be a valid SPDX license expression
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.1.3 (node_modules/fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.1.3: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})

npm ERR! file sh
npm ERR! code ELIFECYCLE
npm ERR! errno ENOENT
npm ERR! syscall spawn
npm ERR! phantomjs-prebuilt@2.1.16 install: `node install.js`
npm ERR! spawn ENOENT
npm ERR! 
npm ERR! Failed at the phantomjs-prebuilt@2.1.16 install script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /root/.npm/_logs/2018-03-31T11_39_28_566Z-debug.log

此時忽略phantomjs-prebuilt@2.1.16，執行命令如下

[root@localhost elasticsearch-head]# npm install phantomjs-prebuilt@2.1.16 --ignore-scripts
npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN elasticsearch-head@0.0.0 license should be a valid SPDX license expression
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.1.3 (node_modules/fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.1.3: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})

+ phantomjs-prebuilt@2.1.16
added 66 packages and removed 4 packages in 18.237s
[root@localhost elasticsearch-head]# ls

啟動elastichsearch-head

npm run start
驗證elasticsearch-head,在瀏覽器中輸入主機地址和埠

重啟elastichsearch

1.當重啟elasticsearch可能會出現以下錯誤， 這個是因為不能將elasticsearch-head放到plugins資料夾下

[a123@localhost bin]$ ./elasticsearch
Picked up _JAVA_OPTIONS: -Xms64m -Xmx64m -Xmn32m
Picked up _JAVA_OPTIONS: -Xms64m -Xmx64m -Xmn32m
Picked up _JAVA_OPTIONS: -Xms64m -Xmx64m -Xmn32m
[2018-03-31T20:25:19,776][WARN ][o.e.b.ElasticsearchUncaughtExceptionHandler] [] uncaught exception in thread [main]
org.elasticsearch.bootstrap.StartupException: java.lang.IllegalArgumentException: property [elasticsearch.version] is missing for plugin [head]
    at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:125) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.bootstrap.Elasticsearch.execute(Elasticsearch.java:112) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124) ~[elasticsearch-cli-6.2.3.jar:6.2.3]
    at org.elasticsearch.cli.Command.main(Command.java:90) ~[elasticsearch-cli-6.2.3.jar:6.2.3]
    at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:92) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:85) ~[elasticsearch-6.2.3.jar:6.2.3]
Caused by: java.lang.IllegalArgumentException: property [elasticsearch.version] is missing for plugin [head]
    at org.elasticsearch.plugins.PluginInfo.readFromProperties(PluginInfo.java:226) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.plugins.PluginInfo.readFromProperties(PluginInfo.java:184) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.bootstrap.Spawner.spawnNativePluginControllers(Spawner.java:75) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:167) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:323) ~[elasticsearch-6.2.3.jar:6.2.3]
    at org.elasticsearch.bootstrap.Elasticsearch.init(Elasticsearch.java:121) ~[elasticsearch-6.2.3.jar:6.2.3]
    ... 6 more

2.當重啟伺服器之後發現依舊如上圖， 還是無法正常連線到elasticsearch服務，這是因為elasticsearch服務與elasticsearch-head之間可能存在跨越，修改elasticsearch配置即可，在elastichsearch.yml中新增如下命名即可：

#allow origin
http.cors.enabled: true
http.cors.allow-origin: "*"

重新連線如下：