Elasticsearch伪集群部署和节点扩容

elasticsearch.jpg

概述

在一台物理机器上部署3个节点的Elasticsearch集群，然后平滑扩容至5个节点

部署过程

下载

wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-5.5.0.tar.gz

解压

tar xvf elasticsearch-5.5.0.tar.gz

复制解压后文件5份

cp -rf elasticsearch-5.5.0 es1 
cp -rf elasticsearch-5.5.0 es2
cp -rf elasticsearch-5.5.0 es3
cp -rf elasticsearch-5.5.0 es4
cp -rf elasticsearch-5.5.0 es5

修改节点1配置

grep -v '^#' es1/config/elasticsearch.yml
cluster.name: AM
node.name: node-1
network.host: 10.86.0.105
http.port: 19201
transport.tcp.port: 19301
discovery.zen.ping.unicast.hosts: ["10.86.0.105:19301", "10.86.0.105:19302", "10.86.0.105:19303"]
discovery.zen.minimum_master_nodes: 2

修改节点2配置

grep -v '^#' es2/config/elasticsearch.yml
cluster.name: AM
node.name: node-2
network.host: 10.86.0.105
http.port: 19202
transport.tcp.port: 19302
discovery.zen.ping.unicast.hosts: ["10.86.0.105:19301", "10.86.0.105:19302", "10.86.0.105:19303"]
discovery.zen.minimum_master_nodes: 2

修改节点3配置

grep -v '^#' es3/config/elasticsearch.yml
cluster.name: AM
node.name: node-3
network.host: 10.86.0.105
http.port: 19203
transport.tcp.port: 19303
discovery.zen.ping.unicast.hosts: ["10.86.0.105:19301", "10.86.0.105:19302", "10.86.0.105:19303"]
discovery.zen.minimum_master_nodes: 2

依次启动3个节点

es1/bin/elasticsearch
es2/bin/elasticsearch
es3/bin/elasticsearch

使用api接口查询Elasticserch状态

http://10.86.0.105:19202/_cat/nodes?v=pretty

Snip20180529_15.png

使用api接口插入一条数据

curl -XPUT 'http://10.86.0.105:19201/blog/user/dilbert' -d '{ "name" : "Dilbert Brown" }'
{"_index":"blog","_type":"user","_id":"dilbert","_version":1,"result":"created","_shards":{"total":3,"successful":2,"failed":0},"created":true}

使用Elasticsearch Head Chrome插件查看集群索引状态

Snip20180529_13.png

扩容过程

修改节点4配置

grep -v '^#' es4/config/elasticsearch.yml
cluster.name: AM
node.name: node-4
network.host: 10.86.0.105
http.port: 19204
transport.tcp.port: 19304
discovery.zen.ping.unicast.hosts: ["10.86.0.105:19301", "10.86.0.105:19302", "10.86.0.105:19303"]
discovery.zen.minimum_master_nodes: 2

修改节点5配置

grep -v '^#' es4/config/elasticsearch.yml
cluster.name: AM
node.name: node-5
network.host: 10.86.0.105
http.port: 19205
transport.tcp.port: 19305
discovery.zen.ping.unicast.hosts: ["10.86.0.105:19301", "10.86.0.105:19302", "10.86.0.105:19303"]
discovery.zen.minimum_master_nodes: 2

依次启动节点4和节点5

es4/bin/elasticsearch
es5/bin/elasticsearch

在master节点(此处为节点2)可看到日志输出如下：

[2018-05-29T14:35:22,151][WARN ][o.e.d.z.ElectMasterService] [node-2] value for setting "discovery.zen.minimum_master_nodes" is too low. This can result in data loss! Please set it to at least a quorum of master-eligible nodes (current value: [2], total number of master-eligible nodes used for publishing in this round: [4])

需要修改discovery.zen.minimum_master_nodes为(N/2)+1，以防止集群脑裂出现多个master节点。(之前3个节点，discovery.zen.minimum_master_nodes为2；扩容后节点数为5，discovery.zen.minimum_master_nodes需修改为3)
使用api接口修改discovery.zen.minimum_master_nodes

curl -XPUT 10.86.0.105:19201/_cluster/settings -d '{
    "persistent" : {
        "discovery.zen.minimum_master_nodes" : 3
    }
}'
{"acknowledged":true,"persistent":{"discovery":{"zen":{"minimum_master_nodes":"3"}}},"transient":{}}

使用api接口查看确认修改生效

http://10.86.0.105:19201/_cluster/settings

Snip20180529_24.png

使用Elasticsearch Head Chrome插件查看集群索引变更为如下状态

Snip20180529_22.png
确认集群discovery.zen.minimum_master_nodes修改生效后，修改每个节点配置文件config/elasticsearch.yml中discovery.zen.minimum_master_nodes为3，并依次重启所有节点即可。