1.elasticsearch单节点部署

1.介绍

1.Lucene

就是一个jar包，里面包含了封装好的各种建立倒排索引，以及进行搜索的代码，包含各种算法，我们就用java开发的时候，引入lucene jar，然后基于lucene的api去进行开发就可以了，

我们就可以将已有的数据数据建立索引，lucene会在本地磁盘上面，给我们组织索引的数据结构。另外的话，我们也可以用lucene提供的的功能和api来针对磁盘上的索引数据，进行搜索。

2.elasticsearch

分布式搜索和分析引擎

Elasticsearch也使用Java开发并使用Lucene作为其核心来实现所有索引和搜索的功能，但是它的目的是通过简单的RESTful API来隐藏Lucene的复杂性，从而让全文搜索变得简单。

总结：

es就是lucene封装了外壳，讲lucene复杂的流程简单化    Elasticsearch不是什么新技术，主要是将全文检索，数据分析以及分布式技术，合并在一起，才形成了独一无二的ES，lucene(全文检索)

2.安装

1.安装java

yum install -y java-1.8.0-openjdk.x86_64

2.下载安装软件

wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-6.6.0.rpm
rpm -ivh elasticsearch-6.6.0.rpm 
warning: elasticsearch-6.6.0.rpm: Header V4 RSA/SHA512 Signature, key ID d88e42b4: NOKEY
Preparing...                          ################################# [100%]
Creating elasticsearch group... OK
Creating elasticsearch user... OK
Updating / installing...
   1:elasticsearch-0:6.6.0-1          ################################# [100%]
### NOT starting on installation, please execute the following statements to configure elasticsearch service to start automatically using systemd
 sudo systemctl daemon-reload
 sudo systemctl enable elasticsearch.service
### You can start elasticsearch service by executing
 sudo systemctl start elasticsearch.service
Created elasticsearch keystore in /etc/elasticsearch

### 配置启动
systemctl daemon-reload
systemctl enable elasticsearch.service
systemctl start elasticsearch.service
systemctl status elasticsearch.service

### 检查是否启动成功
[ soft]# netstat -lntup |grep 9200
tcp6       0      0 127.0.0.1:9200          :::*                    LISTEN      10317/java          
tcp6       0      0 ::1:9200                :::*                    LISTEN      10317/java          
[ soft]# curl 127.0.0.1:9200
{
  "name" : "ixFqenL",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "IOiVybhlTe6X6j1YUNOrMA",
  "version" : {
    "number" : "6.6.0",
    "build_flavor" : "default",
    "build_type" : "rpm",
    "build_hash" : "a9861f4",
    "build_date" : "2019-01-24T11:27:09.439740Z",
    "build_snapshot" : false,
    "lucene_version" : "7.6.0",
    "minimum_wire_compatibility_version" : "5.6.0",
    "minimum_index_compatibility_version" : "5.0.0"
  },
  "tagline" : "You Know, for Search"
}

3.配置文件

rpm -ql elasticsearch		#查看elasticsearch软件安装了哪些目录
rpm -qc elasticsearch		#查看elasticsearch的所有配置文件

/etc/elasticsearch/elasticsearch.yml    #配置文件
/etc/elasticsearch/jvm.options.            #jvm虚拟机配置文件
/etc/init.d/elasticsearch  		#init启动文件
/etc/sysconfig/elasticsearch		#环境变量配置文件
/usr/lib/sysctl.d/elasticsearch.conf	#sysctl变量文件，修改最大描述符
/usr/lib/systemd/system/elasticsearch.service  #systemd启动文件
/var/lib/elasticsearch		# 数据目录
/var/log/elasticsearch		#日志目录
/var/run/elasticsearch		#pid目录

1.修改配置文件
[ soft]# grep "^[a-Z]"  /etc/elasticsearch/elasticsearch.yml 
##节点名node.name: node-1
##数据目录    
path.data: /data/elasticsearch
##日志目录
path.logs: /var/log/elasticsearch
##锁内存，提前占用内存
bootstrap.memory_lock: true
##网络ip，不配置默认为127.0.0.1，这样只能自己访问
network.host: 192.168.100.29
##端口，默认9200
http.port: 9200
2.查看最大最小内存
[ soft]# vi /etc/elasticsearch/jvm.options 
-Xms1g
-Xmx1g

官方文档   内存限制：
1.不要超过32G 
2.最大最小设置一样
3.配置文件设置锁定内存
4.至少给服务器本身空余50%的内存



3.创建数据目录
mkdir /data/elasticsearch
##因为es会自动创建用户，所以需要讲目录给他，不然写不了数据
chown -R elasticsearch:elasticsearch /data/elasticsearch/

4.启动   此时会失败
tail -f /var/log/elasticsearch/elasticsearch.log 
[1]: memory locking requested for elasticsearch process but memory is not locked

官方解决方法：
### 修改启动配置文件或创建新配置文件
方法1: systemctl edit elasticsearch
方法2: vim /usr/lib/systemd/system/elasticsearch.service 
### 增加如下参数
[Service]
LimitMEMLOCK=infinity

### 重新启动
systemctl daemon-reload
systemctl restart elasticsearch
5.配置完成
[ ~]# netstat -lntup |grep 9200
tcp6       0      0 192.168.100.29:9200     :::*                    LISTEN      10848/java          
[ ~]# curl 192.168.100.29:9200
{
  "name" : "node-1",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "q04N04iKQ-KaU8_KPCLJBw",
  "version" : {
    "number" : "6.6.0",
    "build_flavor" : "default",
    "build_type" : "rpm",
    "build_hash" : "a9861f4",
    "build_date" : "2019-01-24T11:27:09.439740Z",
    "build_snapshot" : false,
    "lucene_version" : "7.6.0",
    "minimum_wire_compatibility_version" : "5.6.0",
    "minimum_index_compatibility_version" : "5.0.0"
  },
  "tagline" : "You Know, for Search"
}

3.head插件安装

vi /etc/elasticsearch/elasticsearch.yml 
http.cors.enabled: true
http.cors.allow-origin: "*"

把head包放入谷歌

Elasticsearch 数据库

=========================

Document 行

Type 表

Index 库

filed 字段

创建索引

curl -XPUT 192.168.100.29:9200/vipinfo?pretty

curl -XPUT ‘192.168.100.29:9200/vipinfo/user/1?pretty‘ -H ‘Content-Type: application/json‘ -d‘
{
    "first_name" : "John",
    "last_name": "Smith",
    "age" : 25,
    "about" : "I love to go rock climbing", "interests": [ "sports", "music" ]
}‘
curl -XPUT  ‘localhost:9200/vipinfo/user/2?pretty‘ -H ‘Content-Type: application/json‘ -d‘ {
"first_name": "Jane",
"last_name" : "Smith",
"age" : 32,
"about" : "I like to collect rock albums", "interests": [ "music" ]
}‘

curl -XPUT  ‘localhost:9200/vipinfo/user/3?pretty‘ -H ‘Content-Type: application/json‘ -d‘ {
"first_name": "Douglas", "last_name" : "Fir",
"age" : 35,
"about": "I like to build cabinets", "interests": [ "forestry" ]
}‘

主键不能重复（id） 不指定为随机生成

随机指定有利于提高效率，因为数据库在插入时会判断是否id重复