【零】简介
Elasticsearch是一个基于Apache Lucene(TM)的开源搜索引擎,分布式,十分高效。
主要的特点:
- 分布式的实时文件存储,每个字段都被索引并可被搜索
- 分布式的实时分析搜索引擎
- 可以扩展到上百台服务器,处理PB级结构化或非结构化数据
【一】下载、安装、启动、安装插件
sudo wget https://download.elasticsearch.org/elasticsearch/release/org/elasticsearch/distribution/zip/elasticsearch/2.1.1/elasticsearch-2.1.1.zip sudo unzip elasticsearch-2.1.1.zip sudo mv /home/username/elasticsearch-2.1.1 /usr/lib/elasticsearch #启动 sudo ./bin/elasticsearch
启动报错
[huanghaifeng@vm20251 elasticsearch]$ sudo ./bin/elasticsearch Exception in thread "main" java.lang.RuntimeException: don't run elasticsearch as root. at org.elasticsearch.bootstrap.Bootstrap.initializeNatives(Bootstrap.java:93) at org.elasticsearch.bootstrap.Bootstrap.setup(Bootstrap.java:144) at org.elasticsearch.bootstrap.Bootstrap.init(Bootstrap.java:285) at org.elasticsearch.bootstrap.Elasticsearch.main(Elasticsearch.java:35) Refer to the log for complete error details.
原因是,ElasticSearch不能作为root启动
sudo chown huanghaifeng elasticsearch sudo chown huanghaifeng elasticsearch/* sudo chown huanghaifeng elasticsearch/log/* ./bin/elasticsearch
用自己的账户开启,Permission denied;用sudo,直接不给开起
检查是否开启
curl 'http://localhost:9200/?pretty' #输出 { "name" : "Torrent", "cluster_name" : "elasticsearch", "version" : { "number" : "2.1.1", "build_hash" : "40e2c53a6b6c2972b3d13846e450e66f4375bd71", "build_timestamp" : "2015-12-15T13:05:55Z", "build_snapshot" : false, "lucene_version" : "5.3.1" }, "tagline" : "You Know, for Search" }
安装插件
./bin/plugin -h ./bin/plugin install mobz/elasticsearch-head ./bin/plugin list #其他常用的插件安装 http://www.cnblogs.com/wgp13x/p/4859680.html
打开http://10.60.81.183:9200/_plugin/head/出现问题,一直是“无法显示此网页”。
解决办法
#检查监听网络 netstat -an #编辑配置文件,添加network.host和http.port vi elasticsearch.yml # ---------------------------------- Network ----------------------------------- # Set the bind address to a specific IP (IPv4 or IPv6): network.host: 10.60.81.183 # Set a custom port for HTTP: http.port: 9200
重启elasticsearch,即可打开网页
最后给出一个对应关系,让读者理解elasticsearch
Relational DB -> Databases -> Tables -> Rows -> Columns
Elasticsearch -> Indices -> Types -> Documents -> Fields
【二】新建索引、简单查询、基本使用
API : curl -X<VERB> '<PROTOCOL>://<HOST>:<PORT>/<PATH>?<QUERY_STRING>' -d '<BODY>'
- VERB HTTP方法:
GET
,POST
,PUT
,HEAD
,DELETE
- PROTOCOL http或者https协议(只有在Elasticsearch前面有https代理的时候可用)
- HOST Elasticsearch集群中的任何一个节点的主机名,如果是在本地的节点,那么就叫localhost
- PORT Elasticsearch HTTP服务所在的端口,默认为9200
- PATH API路径(例如_count将返回集群中文档的数量),PATH可以包含多个组件,例如_cluster/stats或者_nodes/stats/jvm
- QUERY_STRING 一些可选的查询请求参数,例如
?pretty
参数将使请求返回更加美观易读的JSON数据 - BODY 一个JSON格式的请求主体(如果请求需要的话)
#插入数据 PUT /megacorp/employee/1 { "first_name" : "John", "last_name" : "Smith", "age" : 25, "about" : "I love to go rock climbing", "interests": [ "sports", "music" ] } #查询数据量 curl -XGET 'http://localhost:9200/_count' -d ' { "query":{ "match_all":{} } }' #查询单个文档详情 curl -XGET http://10.60.81.183:9200/megacorp/employee/1?pretty #简单查询接口调用 GET /megacorp/employee/_search?pretty #添加条件检索 curl -XGET http://10.60.81.183:9200/megacorp/employee/_search?q=last_name:Smith