插件能额外扩展elasticsearch功能，提供各类功能等等。有三种类型的插件：

1. java插件
   只包含JAR文件，必须在集群中每个节点上安装而且需要重启才能使插件生效。
2. 网站插件
   这类插件包含静态web内容，如js、css、html等等，可以直接从elasticsearch服务，如head插件。只需在一个节点上安装，不需要重启服务。可以通过下面的URL访问，如：http://node-ip:9200/_plugin/plugin_name
3. 混合插件
   顾名思义，就是包含上面两种的插件。

插件管理

# ./bin/plugin -h
SYNOPSIS
    plugin <command>
COMMANDS
    install    Install a plugin
    remove     Remove a plugin
    list       List installed plugins
NOTES
    [*] For usage help on specific commands please type "plugin <command> -h"

插件安装

# ./bin/plugin install -h
NAME
    install - Install a plugin
SYNOPSIS
    plugin install <name or url>
DESCRIPTION
    This command installs an elasticsearch plugin. It can be used as follows:
    Officially supported or commercial plugins require just the plugin name:

        plugin install analysis-icu
        plugin install shield

    Plugins from GitHub require 'username/repository' or 'username/repository/version':

        plugin install lmenezes/elasticsearch-kopf
        plugin install lmenezes/elasticsearch-kopf/1.5.7

    Plugins from Maven Central or Sonatype require 'groupId/artifactId/version':

        plugin install org.elasticsearch/elasticsearch-mapper-attachments/2.6.0

    Plugins can be installed from a custom URL or file location as follows:

        plugin install http://some.domain.name//my-plugin-1.0.0.zip
        plugin install file:/path/to/my-plugin-1.0.0.zip

OFFICIAL PLUGINS
    The following plugins are officially supported and can be installed by just referring to their name
    - analysis-icu
    - analysis-kuromoji
    - analysis-phonetic
    - analysis-smartcn
    - analysis-stempel
    - cloud-aws
    - cloud-azure
    - cloud-gce
    - delete-by-query
    - discovery-multicast
    - lang-javascript
    - lang-python
    - mapper-murmur3
    - mapper-size

OPTIONS
    -t,--timeout                 Timeout until the plugin download is abort
    -v,--verbose                 Verbose output
    -h,--help                    Shows this message

安装head插件

bin/plugin install mobz/elasticsearch-head

安装中文分词插件ik，请参加之前的文章。

安装Marvel插件

# bin/plugin install license
# bin/plugin install marvel-agent

这个插件已经集成到kibana上了，kibana内容后续再说，还需要在kibana上安装Marvel插件

# bin/kibana plugin --install elasticsearch/marvel/latest

Marvel是收费的，监控工具，推荐使用。2.0版本会报NullPointerException错误，还未找到解决方法。

查看已安装的插件

# ./bin/plugin  list

删除插件

# ./bin/plugin remove plugin_name

关于插件更多内容参见：https://www.elastic.co/guide/en/elasticsearch/plugins/2.0/index.html

elasticsearch的内容暂且更新这么多了，转到kibana上去了，目前这些内容够你摆弄ELK。后面再回过头来继续elasticsearch内容，如增删查改等等。