CentOS7下Elasticsearch集群部署记录

之前在三台服务器部署Elasticsearch集群：
qd-vpc-op-es01    101.119.92.247
qd-vpc-op-es02    101.119.92.249
qd-vpc-op-es03    101.119.92.254

下面再追加一台es04机器到集群中，操作如下：
qd-vpc-op-es04    101.119.92.16

1）安装jdk和elasticsearch
jdk-8u5-linux-x64.rpm下载地址：
https://pan.baidu.com/s/1bpxtX5X      (提取密码：df6s)

elasticsearch-5.5.0.rpm下载地址：
https://pan.baidu.com/s/1mibwWeG     （提取密码：vtm2）

[root@qd-vpc-op-es04 ~]# cd tools/
[root@qd-vpc-op-es04 tools]# ls
elasticsearch-5.5.0.rpm  jdk-8u5-linux-x64.rpm
[root@qd-vpc-op-es04 tools]# rpm -ivh elasticsearch-5.5.0.rpm 
[root@qd-vpc-op-es04 tools]# rpm -ivh jdk-8u5-linux-x64.rpm 
[root@qd-vpc-op-es04 tools]# java -version
java version "1.8.0_05"
Java(TM) SE Runtime Environment (build 1.8.0_05-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.5-b02, mixed mode)

2）配置elasticsearch
[root@qd-vpc-op-es04 ~]# cd /etc/elasticsearch/
[root@qd-vpc-op-es04 elasticsearch]# ls
elasticsearch.yml  elasticsearch.yml.bak  jvm.options  log4j2.properties  nohup.out  scripts

[root@qd-vpc-op-es04 elasticsearch]# cat elasticsearch.yml|grep -v "#"           //集群中每个节点的配置内容都基本一致

cluster.name: image_search                                                       //集群名称
node.name: image_search_node_4                                                   //集群中本节点的节点名称，这里定义即可
path.data: /data/es/data                                                         //服务目录路径
path.logs: /data/es/logs                                                         //服务日志路径
discovery.zen.ping.unicast.hosts: ["101.119.92.247","101.119.92.249","101.119.92.254","10.111.233.16"]     //这里是各节点的ip地址
network.host: 0.0.0.0                                                            //服务绑定的网络地址

默认elasticsearch服务端口时9200
[root@qd-vpc-op-es04 elasticsearch]# cat elasticsearch.yml|grep 9200
#http.port: 9200

[root@qd-vpc-op-es04 elasticsearch]# systemctl start elasticsearch.service
[root@qd-vpc-op-es04 elasticsearch]# systemctl restart elasticsearch.service
[root@qd-vpc-op-es04 elasticsearch]# systemctl status elasticsearch.service

[root@qd-vpc-op-es04 elasticsearch]# ps -ef|grep elasticsearch
[root@qd-vpc-op-es04 elasticsearch]# lsof -i:9200
COMMAND   PID          USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
java    10998 elasticsearch  320u  IPv4  39255      0t0  TCP *:wap-wsp (LISTEN)

检查elasticsearch的健康状态
[root@qd-vpc-op-es04 elasticsearch]# curl ‘localhost:9200/_cat/indices?v‘
health status index                   uuid                   pri rep docs.count docs.deleted store.size pri.store.size
green  open   video_filter            Bx7He6ZtTEWuRBqXYC6gRw   5   1     458013            0      4.1gb            2gb
green  open   recommend_history_image svYo_Do4SM6wUiv6taUWug   5   1    2865902            0     24.9gb         12.4gb
green  open   recommend_history_gif   rhN3MDN2TbuYILqEDksQSg   5   1     265731            0      2.4gb          1.2gb
green  open   post_images             TMsMsMEoR5Sdb7UEQJsR5Q   5   1   48724932            0    407.3gb        203.9gb
green  open   review_images_v2        qzqnknpgTniU4rCsvXzs0w   5   1   50375955            0     61.6gb         30.9gb
green  open   review_images           rWC4WlfMS8aGe-GOkTauZg   5   1   51810877            0    439.3gb        219.7gb
green  open   sensitive_images        KxSrjvXdSz-y8YcqwBMsZA   5   1      13393            0    128.1mb           64mb
green  open   post_images_v2          FDphBV4-QuKVoD4_G3vRtA   5   1   49340491            0     55.8gb         27.8gb

从上面的命令结果中可以看出，本节点已经成功加入到名为image_search的elasticsearch集群中了，green表示节点状态很健康，数据也已经在同步中了。

3）在代码中更新elasticsearch的配置
通知开发同事，在代码中增加新增elasticsearch节点的配置，上线更新后，到新节点上查看elasticsearch日志是否有信息写入：
[root@qd-vpc-op-es04 ~]# cd /data/es/logs/
[root@qd-vpc-op-es04 ~]# chown -R elasticsearch.elasticsearch /data/es
[root@qd-vpc-op-es04 logs]# ls
image_search_deprecation.log  image_search_index_indexing_slowlog.log  image_search_index_search_slowlog.log  image_search.log

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注意：
如果往elasticsearch集群中新增一个节点，做法如下：
1）在新节点上安装jdk和elasticsearch服务，配置elasticsearch.yml文件了，启动elasticsearch服务
2）在集群中其他节点上配置elasticsearch.yml文件，不需要启动elasticsearch服务
3）在新节点上执行curl ‘localhost:9200/_cat/indices?v‘命令，查看健康状态以及数据同步情况
4）在代码中增加新增elasticsearch节点的配置，上线更新后，查看新增节点的elasticsearch日志是否有信息写入
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最后顺便贴一下其他三个节点的elasticsearch.yml文件配置：
[root@qd-vpc-op-es01 ~]# cat /etc/elasticsearch/elasticsearch.yml |grep -v "#"

cluster.name: image_search
node.name: image_search_node_1
path.data: /data/es/data
path.logs: /data/es/logs
discovery.zen.ping.unicast.hosts: ["10.111.233.16","101.119.92.247","101.119.92.249","101.119.92.254"]
network.host: 0.0.0.0

[root@qd-vpc-op-es02 ~]# cat /etc/elasticsearch/elasticsearch.yml |grep -v "#"
cluster.name: image_search
node.name: image_search_node_2
path.data: /data/es/data
path.logs: /data/es/logs
discovery.zen.ping.unicast.hosts: ["10.111.233.16","101.119.92.247","101.119.92.249","101.119.92.254"]
network.host: 0.0.0.0

[root@qd-vpc-op-es03 ~]# cat /etc/elasticsearch/elasticsearch.yml|grep -v "#"

cluster.name: image_search
node.name: image_search_node_3
path.data: /data/es/data
path.logs: /data/es/logs
discovery.zen.ping.unicast.hosts: ["101.119.92.247","101.119.92.249","101.119.92.254","10.111.233.16"]
network.host: 0.0.0.0
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如果关闭某个节点或将其从集群中提出来，需要提前通知该节点停止同步数据（迁移的时候会用到）：
# curl -XPUT ‘localhost:9200/_cluster/settings‘ -d ‘{"transient" : {"cluster.routing.allocation.enable" : "none”}}’