ElasticSearch集群搭建

es天然支持集群模式，其好处主要有两个：
1.能够增大系统的容量，如内存、磁盘，使得 es集群可以支持PB级的数据；
2.能够提高系统可用性，即使部分节点停止服务，整个集群依然可以正常服务；

ELasticsearch 集群是由多个节点组成的，通过cluster.name 设置集群名称，并且用于区分其它的集群，每个节点通过 node.name 指定节点的名称

# yum install java -y
# rpm -ivh elasticsearch-7.8.1-x86_64.rpm

[root@es-node1 ~]# vim /etc/elasticsearch/elasticsearch.yml 
[root@es-node1 ~]# grep "^[a-zA-Z]" /etc/elasticsearch/elasticsearch.yml 
cluster.name: my-application # 集群名称，所有参加集群的节点集群名称应该保持一致
node.name: es-node1 # 节点名称
path.data: /var/lib/elasticsearch # es数据存储路径
path.logs: /var/log/elasticsearch  # es日志存储路径

#bootstrap.memory_lock: true # 不使用swap分区

network.host: 172.16.1.161 # 监听在本地ip
http.port: 9200 # 监听在本地端口
discovery.seed_hosts: ["172.16.1.161", "172.16.1.162","172.16.1.163"] #集群主机列表
cluster.initial_master_nodes: ["172.16.1.161", "172.16.1.162","172.16.1.163"] # 仅第一次启动集群时对列表中的主机进行选举

[root@es-node2 ~]# grep "^[a-zA-Z]" /etc/elasticsearch/elasticsearch.yml 
cluster.name: my-application
node.name: es-node2
path.data: /var/lib/elasticsearch
path.logs: /var/log/elasticsearch
network.host: 172.16.1.162
http.port: 9200
discovery.seed_hosts: ["172.16.1.161", "172.16.1.162","172.16.1.163"]
cluster.initial_master_nodes: ["172.16.1.161", "172.16.1.162","172.16.1.163"]

[root@es-node3 ~]# grep "^[a-zA-Z]" /etc/elasticsearch/elasticsearch.yml 
cluster.name: my-application
node.name: es-node3
path.data: /var/lib/elasticsearch
path.logs: /var/log/elasticsearch
network.host: 172.16.1.163
http.port: 9200
discovery.seed_hosts: ["172.16.1.161", "172.16.1.162","172.16.1.163"]
cluster.initial_master_nodes: ["172.16.1.161", "172.16.1.162","172.16.1.163"]