在ElasticSearch2.0之后的版本中没有默认的delete-by-query，想使用此命令需要安装这个插件。
首先需要进入ES的目录
[root@node122 elasticsearch]# pwd
/usr/share/elasticsearch
# bin/plugin install delete-by-query -> Installing delete-by-query... Trying https://download.elastic.co/elasticsearch/release/org/elasticsearch/plugin/delete-by-query/2.4.1/delete-by-query-2.4.1.zip ... Downloading ...........DONE Verifying https://download.elastic.co/elasticsearch/release/org/elasticsearch/plugin/delete-by-query/2.4.1/delete-by-query-2.4.1.zip checksums if available ... Downloading .DONE Installed delete-by-query into /usr/share/elasticsearch/plugins/delete-by-query
