问题：

下载对应版本ik,按照readme.mp提示安装：

Install
1.download or compile
optional 1 - download pre-build package from here: https://github.com/medcl/elasticsearch-analysis-ik/releases
create plugin folder cd your-es-root/plugins/ && mkdir ik
unzip plugin to folder your-es-root/plugins/ik

optional 2 - use elasticsearch-plugin to install ( supported from version v5.5.1 ):
./bin/elasticsearch-plugin install https://github.com/medcl/elasticsearch-analysis-ik/releases/download/v6.3.0/elasticsearch-analysis-ik-6.3.0.zip
NOTE: replace 6.3.0 to your own elasticsearch version

2.restart elasticsearch

报错：

Caused by: java.lang.IllegalStateException: Could not load plugin descriptor for plugin directory [ik]
Caused by: java.nio.file.NoSuchFileException: D:\elasticsearch-7.6.0\ plugins\ik\plugin-descriptor.properties

解决办法：

缺少了如下步骤：

cd elasticsearch-analysis-ik
mvn clean
mvn compile
mvn package