背景：目前国内有大量的公司都在使用 Elasticsearch，包括阿里、京东、滴滴、今日头条、小米、vivo等诸多知名公司。除了搜索功能之外，Elasticsearch还结合Kibana、Logstash、Elastic Stack还被广泛运用在大数据近实时分析领域，包括日志分析、指标监控等多个领域。
本节内容：今天终于迎来了大家期待已久的ElasticSearch集群搭建。
目录
前提说明：实际生产业务场景下，集群模式会有多台物理机支撑。但由于老王机器有限，所以就搭建一个伪集群环境，即在一台MAC上部署3个应用，但原理与多台机器是类似的。
1、Elastcsearch版本下载及安装
我用的是Elasticsearch-7.9.3版本，下载及安装过程参考前面文章 Elasticsearch各版本特性。
2、本地集群搭建步骤
2.1 节点复制
通过压缩包解压出三份，分别命名为：
elasticsearch-7.9.3、
elasticsearch-7.9.3.2、
elasticsearch-7.9.3.3。
注意：一定要使用干净的压缩文件解压出3份，防止数据污染。
如下图所示，
2.2 节点YML配置修改
主要针对解压目录下的 config/elasticsearch.yml 进行修改。
主要修改以下部分：
#集群名，所有节点需要保持集群名一样
cluster.name: my-cluster
#节点名，每个节点名称不同
node.name: node01
#host配置
network.host: 127.0.0.1
#HTTP 请求端口，每个节点不同
http.port: 9201
#TCP请求端口，每个节点不同
transport.tcp.port: 9301
#设置这个参数来保证集群中的节点可以知道其它N个有master资格的节点。默认为1，对于大的集群来说，可以设置大一点的值（2-4）
discovery.zen.minimum_master_nodes: 2
#首先遍历discovery.seed_hosts 以及最后通信的cluster的符合主节点选举条件的主机列表
discovery.seed_hosts: ["127.0.0.1:9301", "127.0.0.1:9302", "127.0.0.1:9303"]
#节点ping超时时间设置
discovery.zen.fd.ping_timeout: 1m
#节点ping重试次数
discovery.zen.fd.ping_retries: 5
# es7.x 之后新增的配置，初始化一个新的集群时，需要此配置来选举master
cluster.initial_master_nodes: ["node01", "node02", "node03"]
# 跨域设置
http.cors.enabled: true
http.cors.allow-origin: "*"
#节点设置，既可以是主节点，又可以为数据节点
node.master: true
node.data: true
2.2.1 节点1配置修改(7.9.3)
# ======================== Elasticsearch Configuration =========================
#
# NOTE: Elasticsearch comes with reasonable defaults for most settings.
# Before you set out to tweak and tune the configuration, make sure you
# understand what are you trying to accomplish and the consequences.
#
# The primary way of configuring a node is via this file. This template lists
# the most important settings you may want to configure for a production cluster.
#
# Please consult the documentation for further information on configuration options:
# https://www.elastic.co/guide/en/elasticsearch/reference/index.html
#
# ---------------------------------- Cluster -----------------------------------
#
# Use a descriptive name for your cluster:
#
cluster.name: my-cluster
#
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
node.name: node01
#
# Add custom attributes to the node:
#
#node.attr.rack: r1
#
# ----------------------------------- Paths ------------------------------------
#
# Path to directory where to store the data (separate multiple locations by comma):
#
#path.data: /path/to/data
#
# Path to log files:
#
#path.logs: /path/to/logs
#
# ----------------------------------- Memory -----------------------------------
#
# Lock the memory on startup:
#
#bootstrap.memory_lock: true
#
# Make sure that the heap size is set to about half the memory available
# on the system and that the owner of the process is allowed to use this
# limit.
#
# Elasticsearch performs poorly when the system is swapping the memory.
#
# ---------------------------------- Network -----------------------------------
#
# Set the bind address to a specific IP (IPv4 or IPv6):
#
network.host: 127.0.0.1
#
# Set a custom port for HTTP:
#
http.port: 9201
transport.tcp.port: 9301
#
# For more information, consult the network module documentation.
#
# --------------------------------- Discovery ----------------------------------
#
# Pass an initial list of hosts to perform discovery when this node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
# 设置这个参数来保证集群中的节点可以知道其它N个有master资格的节点。默认为1，对于大的集群来说，可以设置大一点的值（2-4）
discovery.zen.minimum_master_nodes: 3
discovery.seed_hosts: ["127.0.0.1:9301", "127.0.0.1:9302", "127.0.0.1:9303"]
discovery.zen.fd.ping_timeout: 1m
discovery.zen.fd.ping_retries: 5
#
# Bootstrap the cluster using an initial set of master-eligible nodes:
#
#cluster.initial_master_nodes: ["node-1", "node-2"]
# es7.x 之后新增的配置，初始化一个新的集群时需要此配置来选举master
cluster.initial_master_nodes: ["node01", "node02", "node03"]
#
# For more information, consult the discovery and cluster formation module documentation.
#
# ---------------------------------- Gateway -----------------------------------
#
# Block initial recovery after a full cluster restart until N nodes are started:
#
#gateway.recover_after_nodes: 3
#
# For more information, consult the gateway module documentation.
#
# ---------------------------------- Various -----------------------------------
#
# Require explicit names when deleting indices:
#
#action.destructive_requires_name: true
http.cors.enabled: true
http.cors.allow-origin: "*"
node.master: true
node.data: true
2.2.2 节点2配置修改(7.9.3.2)
# ======================== Elasticsearch Configuration =========================
#
# NOTE: Elasticsearch comes with reasonable defaults for most settings.
# Before you set out to tweak and tune the configuration, make sure you
# understand what are you trying to accomplish and the consequences.
#
# The primary way of configuring a node is via this file. This template lists
# the most important settings you may want to configure for a production cluster.
#
# Please consult the documentation for further information on configuration options:
# https://www.elastic.co/guide/en/elasticsearch/reference/index.html
#
# ---------------------------------- Cluster -----------------------------------
#
# Use a descriptive name for your cluster:
#
cluster.name: my-cluster
#
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
node.name: node02
#
# Add custom attributes to the node:
#
#node.attr.rack: r1
#
# ----------------------------------- Paths ------------------------------------
#
# Path to directory where to store the data (separate multiple locations by comma):
#
#path.data: /path/to/data
#
# Path to log files:
#
#path.logs: /path/to/logs
#
# ----------------------------------- Memory -----------------------------------
#
# Lock the memory on startup:
#
#bootstrap.memory_lock: true
#
# Make sure that the heap size is set to about half the memory available
# on the system and that the owner of the process is allowed to use this
# limit.
#
# Elasticsearch performs poorly when the system is swapping the memory.
#
# ---------------------------------- Network -----------------------------------
#
# Set the bind address to a specific IP (IPv4 or IPv6):
#
network.host: 127.0.0.1
#
# Set a custom port for HTTP:
#
http.port: 9202
transport.tcp.port: 9302
#
# For more information, consult the network module documentation.
#
# --------------------------------- Discovery ----------------------------------
#
# Pass an initial list of hosts to perform discovery when this node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
# 设置这个参数来保证集群中的节点可以知道其它N个有master资格的节点。默认为1，对于大的集群来说，可以设置大一点的值（2-4）
discovery.zen.minimum_master_nodes: 2
# es7.x 之后新增的配置，写入候选主节点的设备地址，在开启服务后可以被选为主节点
discovery.seed_hosts: ["127.0.0.1:9301", "127.0.0.1:9302", "127.0.0.1:9303"]
discovery.zen.fd.ping_timeout: 1m
discovery.zen.fd.ping_retries: 5
#
# Bootstrap the cluster using an initial set of master-eligible nodes:
#
# es7.x 之后新增的配置，初始化一个新的集群时需要此配置来选举master
cluster.initial_master_nodes: ["node01", "node02", "node03"]
#
# For more information, consult the discovery and cluster formation module documentation.
#
# ---------------------------------- Gateway -----------------------------------
#
# Block initial recovery after a full cluster restart until N nodes are started:
#
#gateway.recover_after_nodes: 3
#
# For more information, consult the gateway module documentation.
#
# ---------------------------------- Various -----------------------------------
#
# Require explicit names when deleting indices:
#
#action.destructive_requires_name: true
http.cors.enabled: true
http.cors.allow-origin: "*"
node.master: true
node.data: true
2.2.3 节点3配置修改(7.9.3.3)
# ======================== Elasticsearch Configuration =========================
#
# NOTE: Elasticsearch comes with reasonable defaults for most settings.
# Before you set out to tweak and tune the configuration, make sure you
# understand what are you trying to accomplish and the consequences.
#
# The primary way of configuring a node is via this file. This template lists
# the most important settings you may want to configure for a production cluster.
#
# Please consult the documentation for further information on configuration options:
# https://www.elastic.co/guide/en/elasticsearch/reference/index.html
#
# ---------------------------------- Cluster -----------------------------------
#
# Use a descriptive name for your cluster:
#
cluster.name: my-cluster
#
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
node.name: node03
#
# Add custom attributes to the node:
#
#node.attr.rack: r1
#
# ----------------------------------- Paths ------------------------------------
#
# Path to directory where to store the data (separate multiple locations by comma):
#
#path.data: /path/to/data
#
# Path to log files:
#
#path.logs: /path/to/logs
#
# ----------------------------------- Memory -----------------------------------
#
# Lock the memory on startup:
#
#bootstrap.memory_lock: true
#
# Make sure that the heap size is set to about half the memory available
# on the system and that the owner of the process is allowed to use this
# limit.
#
# Elasticsearch performs poorly when the system is swapping the memory.
#
# ---------------------------------- Network -----------------------------------
#
# Set the bind address to a specific IP (IPv4 or IPv6):
#
network.host: 127.0.0.1
#
# Set a custom port for HTTP:
#
http.port: 9203
transport.tcp.port: 9303
#
# For more information, consult the network module documentation.
#
# --------------------------------- Discovery ----------------------------------
#
# Pass an initial list of hosts to perform discovery when this node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
discovery.zen.minimum_master_nodes: 2
# es7.x 之后新增的配置，写入候选主节点的设备地址，在开启服务后可以被选为主节点
discovery.seed_hosts: ["127.0.0.1:9301", "127.0.0.1:9302", "127.0.0.1:9303"]
discovery.zen.fd.ping_timeout: 1m
discovery.zen.fd.ping_retries: 5
#
# Bootstrap the cluster using an initial set of master-eligible nodes:
#
#cluster.initial_master_nodes: ["node-1", "node-2"]
cluster.initial_master_nodes: ["node01", "node02", "node03"]
#
# For more information, consult the discovery and cluster formation module documentation.
#
# ---------------------------------- Gateway -----------------------------------
#
# Block initial recovery after a full cluster restart until N nodes are started:
#
#gateway.recover_after_nodes: 3
#
# For more information, consult the gateway module documentation.
#
# ---------------------------------- Various -----------------------------------
#
# Require explicit names when deleting indices:
#
#action.destructive_requires_name: true
http.cors.enabled: true
http.cors.allow-origin: "*"
node.master: true
node.data: true
2.3 节点启动
如果之前启动过Elasticsearch节点，则需要先停止。
停止命令，
$ jps | grep Elasticsearch #查询es进程
76665 Elasticsearch
$ kill -SIGTERM 76665 #杀死指定进程
启动命令，
$ cd elasticsearch-7.9.3 #根目录
$ ./bin/elasticsearch -d #启动命令
2.4 Head验证集群
如果还没有安装head，请参考前面的内容 Mac/Windows安装ElasticSearch可视化Head插件
出现以上内容，则表示集群安装成功。
看主节点信息，表示node01被选为了主节点。
除此之外，在head页面还可以查看索引，数据简单查询、数据复合查询。基本能满足我们日常查询需要。
至此，本地集群搭建完成。