ELK集群搭建
准备两台机器，定义node1、node2
资源前置阶段
kibana、es下载地址:
curl -L -O https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-7.5.1-linux-x86_64.tar.gz
curl -L -O https://artifacts.elastic.co/downloads/kibana/kibana-7.5.1-linux-x86_64.tar.gz
新增用户
# 创建elastic用户
useradd elastic
# 设置用户密码
passwd elastic
# 切换到elastic用户
su elastic
elasticsearch集群搭建
下载后解压，编辑conf/elasticsearch.yml文件
1. 修改配置文件
# ======================== 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-application
#
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
node.name: node-1
#
# 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: /home/elastic/elasticsearch/data
#
# Path to log files:
#
path.logs: /home/elastic/elasticsearch/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: 192.168.28.129
#
# Set a custom port for HTTP:
#
http.port: 9200
#
# 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.seed_hosts: ["192.168.28.129", "192.168.28.130", "192.168.28.131"]
#
# Bootstrap the cluster using an initial set of master-eligible nodes:
#
cluster.initial_master_nodes: ["node-1", "node-2", "node-3"]
#
# 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
#
# ---------------------------------- xpack -------------------------------------
#
xpack.monitoring.collection.enabled: true
xpack.security.enabled: true
xpack.monitoring.collection.enabled: true
xpack.security.transport.ssl.enabled: true
xpack.security.transport.ssl.verification_mode: certificate
xpack.security.transport.ssl.keystore.path: elastic-certificates.p12
xpack.security.transport.ssl.truststore.path: elastic-certificates.p12
主要修改如下几处配置：
cluster.name：集群的名称，集群中所有节点的 cluster.name 的值必须要相同。
node.name：集群中每个Elasticsearch的节点名称，不可以重复。
path.data：设置存放Elasticsearch索引文件数据的路径。
path.logs：设置存放日志文件的路径。
network.host：Elasticsearch绑定的IP，外界可以通过这个IP访问到当前Elasticsearch节点，一般配配置当前系统的IP，或者 0.0.0.0 （任何地址都能访问到）。
http.port：当前启动Elasticsearch的端口号，一般默认 9200 即可，当然你也可以修改
discovery.seed_hosts：配置所有Elasticsearch节点绑定的IP地址。
cluster.initial_master_nodes：配置那些节点可以有资格被选为主节点。
xpack.monitoring.collection.enabled：收集监控数据默认为false不收集监控数据。
elasticsearch集群安全配置
1.为集群创建认证机构
文件根目录下执行 bin/elasticsearch-certutil ca
依次输入回车（文件使用默认名），密码
2.为节点颁发证书
复制生成的elastic-stack-ca.p12文件至每个节点，并执行bin/elasticsearch-certutil cert --ca elastic-stack-ca.p12生成证书
依次输入上一个步骤的密码。回车（文件使用默认名），密码（建议与上一步密码相同）
如果有有设置密码，执行以下命令保存密码
bin/elasticsearch-keystore add xpack.security.transport.ssl.keystore.secure_password 第一步输入的密码
bin/elasticsearch-keystore add xpack.security.transport.ssl.truststore.secure_password 第一步输入的密码
4.修改配置
在/config/elasticsearch.yml中增加一下配置，启用x-pack安全组件，启用ssl加密通信，并且配置认证证书：
#---------------------security------------------
#
xpack.security.enabled: true
xpack.security.transport.ssl.enabled: true
xpack.security.transport.ssl.verification_mode: certificate
xpack.security.transport.ssl.keystore.path: elastic-certificates.p12
xpack.security.transport.ssl.truststore.path: elastic-certificates.p12
配置修改完成后，重启es服务，重启成功后
http://192.168.1.100:9200/ 访问Es服务要输入用户名和密码。
5.密码设置
通过设置访问密码，这是elastic用户和其他一些系统内置用户的密码
bin/elasticsearch-setup-passwords interactive
FAQ
错误: max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
解决方案：
echo "vm.max_map_count=262144" > /etc/sysctl.conf
sysctl -p