Elasticsearch配置文件详解

elasticsearch.yml基本配置说明

· elasticsearch

一、基本配置
elasticsearch的config文件夹里面有两个配置文 件：elasticsearch.yml和logging.yml，第一个是es的基本配置文件，第二个是日志配置文件，es也是使用log4j来记录日 志的，所以logging.yml里的设置按普通log4j配置文件来设置就行了。下面主要讲解下elasticsearch.yml这个文件中可配置的东西。

• 只是挑些重要的配置选项进行注释,其实自带的已经有非常细致的英文注释了!

• https://www.elastic.co/guide/en/elasticsearch/reference/current/modules.htm

 ################################### Cluster ###################################   

# 代表一个集群,集群中有多个节点,其中有一个为主节点,这个主节点是可以通过选举产生的,主从节点是对于集群内部来说的.   

# es的一个概念就是去中心化,字面上理解就是无中心节点,这是对于集群外部来说的,因为从外部来看es集群,在逻辑上是个整体,你与任何一个节点的通信和与整个es集群通信是等价的

cluster.name: elasticsearch

配置es的集群名称，默认是elasticsearch，es会自动发现在同一网段下的es，如果在同一网段下有多个集群，就可以用这个属性来区分不同的集群，cluster.name就成为同一个集群的标识。

node.name: "Franz Kafka"

节点名，默认随机指定一个name列表中名字，该列表在es的jar包中config文件夹里name.txt文件中，其中有很多作者添加的有趣名字，节点名称同理,可自动生成也可手动配置。

node.master: true

指定该节点是否有资格被选举成为node，默认是true，es是默认集群中的第一台机器为master，如果这台机挂了就会重新选举master。

node.data: true

指定该节点是否存储索引数据，默认为true。

1. # 配置文件中给出了三种配置高性能集群拓扑结构的模式,如下：   

2. # 1. 如果你想让节点从不选举为主节点,只用来存储数据,可作为负载器   

3. # node.master: **false**   

4. # node.data: **true**   

5. # node.ingest: **false**  

6.   

7. # 2. 如果想让节点成为主节点,且不存储任何数据,并保有空闲资源,可作为协调器   

8. # node.master: **true**   

9. # node.data: **false**  

10. # node.ingest: **false**   

11.   

12. # 3. 如果想让节点既不称为主节点,又不成为数据节点,那么可将他作为搜索器,从节点中获取数据,生成搜索结果等   

13. # node.master: **false**   

14. # node.data: **false**   

15. # node.ingest: **true** (可不指定默认开启)  

16.   

17. # 4. 仅作为协调器   

18. # node.master: **false**   

19. # node.data: **false**  

20. # node.ingest: **false**  

index.number_of_shards: 5

设置默认索引分片个数，默认为5片。

index.number_of_replicas: 1

设置默认索引副本个数，默认为1个副本。

1. # 配置文件中提到的最佳实践是,如果服务器够多,可以将分片提高,尽量将数据平均分布到大集群中去  

2. # 同时,如果增加副本数量可以有效的提高搜索性能   

3. # 需要注意的是,"number_of_shards" 是索引创建后一次生成的,后续不可更改设置   

4. # "number_of_replicas" 是可以通过API去实时修改设置的 

path.conf: /path/to/conf

设置配置文件的存储路径，默认是es根目录下的config文件夹。

path.data: /path/to/data

设置索引数据的存储路径，默认是es根目录下的data文件夹，可以设置多个存储路径，用逗号隔开，例：

path.data: /path/to/data1,/path/to/data2

path.work: /path/to/work

设置临时文件的存储路径，默认是es根目录下的work文件夹。

path.logs: /path/to/logs

设置日志文件的存储路径，默认是es根目录下的logs文件夹

path.plugins: /path/to/plugins

设置插件的存放路径，默认是es根目录下的plugins文件夹

bootstrap.memory_lock：

服务器发生系统swapping的时候ES节点的性能会非常差，也会影响节点的稳定性。所以要不惜一切代价来避免swapping。swapping会导致Java GC的周期延迟从毫秒级恶化到分钟，更严重的是会引起节点响应延迟甚至脱离集群。

这个参数的目的是当你无法关闭系统的swap的时候，建议把这个参数设为true。防止在内存不够用的时候，elasticsearch的内存被交换至交换区，导致性能骤降

bootstrap.mlockall: true

设置为true来锁住内存。因为当jvm开始swapping时es的效率会降低，所以要保证它不swap，可以把ES_MIN_MEM和 ES_MAX_MEM两个环境变量设置成同一个值，并且保证机器有足够的内存分配给es。同时也要允许elasticsearch的进程可以锁住内存，linux下可以通过`ulimit -l unlimited`命令。

network.bind_host: 192.168.0.1

设置绑定的ip地址，可以是ipv4或ipv6的，默认为0.0.0.0。

network.publish_host: 192.168.0.1

设置其它节点和该节点交互的ip地址，如果不设置它会自动判断，值必须是个真实的ip地址。

network.host: 192.168.0.1

这个参数是用来同时设置bind_host和publish_host上面两个参数。

transport.tcp.port: 9300

设置节点间交互的tcp端口，默认是9300。

transport.tcp.compress: true

设置是否压缩tcp传输时的数据，默认为false，不压缩。

http.port: 9200

设置对外服务的http端口，默认为9200。

http.max_content_length: 100mb

设置内容的最大容量，默认100mb

http.enabled: false

是否使用http协议对外提供服务，默认为true，开启。

1. ###################### 使用head等插件监控集群信息，需要打开以下配置项 ###########  

2. # http.cors.enabled: **true**  

3. # http.cors.allow-origin: "*"  

4. # http.cors.allow-credentials: **true** 

1. # 下面的配置控制怎样以及何时启动一整个集群重启的初始化恢复过程   

2. # (当使用shard gateway时,是为了尽可能的重用local data(本地数据))  

gateway.type: local

gateway的类型，默认为local即为本地文件系统，可以设置为本地文件系统，分布式文件系统，Hadoop的HDFS，和amazon的s3服务器。

gateway.recover_after_nodes: 1

集群中N个节点启动后进行数据恢复，默认为1。

gateway.recover_after_time: 5m

设置初始化恢复过程的超时时间,超时时间从上一个配置中配置的N个节点启动后算起，默认是5分钟。

gateway.expected_nodes: 2

设置这个集群中节点的数量，默认为2，一旦这N个节点启动，就会立即进行数据恢复。

1. # 下面这些配置允许在初始化恢复,副本分配,再平衡,或者添加和删除节点时控制节点间的分片分配   

2. # 设置一个节点的并行恢复数 

cluster.routing.allocation.node_initial_primaries_recoveries: 4

初始化数据恢复时，并发恢复线程的个数，默认为4。

cluster.routing.allocation.node_concurrent_recoveries: 2

添加删除节点或负载均衡时并发恢复线程的个数，默认为4。

indices.recovery.max_size_per_sec: 0

设置数据恢复时限制的带宽，如入100mb，默认为0，即无限制。

indices.recovery.concurrent_streams: 5

设置这个参数来限制从其它分片恢复数据时最大同时打开并发流的个数，默认为5。

discovery.zen.minimum_master_nodes: 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.ping.timeout: 3s

设置集群中自动发现其它节点时ping连接超时时间，默认为3秒，对于比较差的网络环境可以高点的值来防止自动发现时出错。

discovery.zen.ping.multicast.enabled: false

设置是否打开多播发现节点，默认是true。

discovery.zen.ping.unicast.hosts: ["host1", "host2:port", "host3[portX-portY]"]

设置集群中master节点的初始列表，可以通过这些节点来自动发现新加入集群的节点。

###节点ping设置，更多等待时间设置discovery.zen.fd.ping_interval：该属性默认为1s（1秒钟），指定了节点互相ping的时间间隔。

discovery.zen.fd.ping_timeout：该属性默认为30s（30秒钟），指定了节点发送ping信息后等待响应的时间，超过此时间则认为对方节点无响应。

discovery.zen.fd.ping_retries：该属性默认为3，指定了重试次数，超过此次数则认为对方节点已停止工作。

1. # 官方插件 相关设置请查看此处  

2. # https://www.elastic.co/guide/en/x-pack/current/xpack-settings.html

下面是一些查询时的慢日志参数设置

index.search.slowlog.level: TRACE

index.search.slowlog.threshold.query.warn: 10s

index.search.slowlog.threshold.query.info: 5s

index.search.slowlog.threshold.query.debug: 2s

index.search.slowlog.threshold.query.trace: 500ms

index.search.slowlog.threshold.fetch.warn: 1s

index.search.slowlog.threshold.fetch.info: 800ms

index.search.slowlog.threshold.fetch.debug:500ms

index.search.slowlog.threshold.fetch.trace: 200ms

二、高级配置（线程池） 一个Elasticsearch节点会有多个线程池，但重要的是下面四个： 索引（index）：主要是索引数据和删除数据操作（默认是cached类型） 搜索（search）：主要是获取，统计和搜索操作（默认是cached类型） 批量操作（bulk）：主要是对索引的批量操作（默认是cached类型） 更新（refresh）：主要是更新操作（默认是cached类型） 可以通过给设置一个参数来改变线程池的类型（type），例如，把索引的线程池改成blocking类型：
min: 1
size: 30
wait_time: 30s

下面是三种可以设置的线程池的类型：
cache
cache线程池是一个无限大小的线程池，如果有很多请求的话都会创建很多线程，下面是个例子：
threadpool:
index:
type: cached

fixed
fixed线程池保持固定个数的线程来处理请求队列。
size参数设置线程的个数，默认设置是cpu核心数的5倍
queue_size可以控制待处理请求队列的大小。默认是设置为-1，意味着无限制。当一个请求到来但队列满了的时候，reject_policy参数可以控制它的行为。默认是abort，会使那个请求失败。设置成caller会使该请求在io线程中执行。
threadpool:
index:
type: fixed
size: 30
queue: 1000
reject_policy: caller

blocking
blocking线程池允许设置一个最小值（min，默认为1）和线程池大小（size，默认为cpu核心数的5倍）。它也有一个等待队列，队列的大小（queue_size ）默认是1000，当这队列满了的时候。它会根据定好的等待时间（wait_time，默认是60秒）来调用io线程，如果超时没有执行就会报错。
threadpool:
index:
type: blocking
min: 1
size: 30
wait_time: 30s

笔者在实际工作中，由于程序启动时即产生大量请求，导致队列大小溢出的情况，从而查询请求报错，可以在以下2个解决方法权衡处理：
1、增加队列长度，但随之带来的是CPU消耗高。
2、优化程序，适当控制程序的并发请求量。

三、操作系统配置
1、文件句柄限制：ES在索引过程中，尤其是有很多分片和副本时，会创建若干文件。因此操作系统对打开文件数量的限制不能少于32000。对于linux服务器，通过可以在/etc/security/limits.conf中进行修改，并且可以用ulimit命令来查看当前值。
2、节点内存配置：ES每个节点默认的2014M内存空间可能是不够的。如果日志文件中有out of memory error错误，则应将环境变量ES_HEAP_SIZE设为大于1024的值。注意该值应超过总可用物理内存的50%，剩余内存可用作磁盘高速缓存，可大大提高搜索性能。

附：ES集群的配置(3台master和3台data节点)

data1

es@spark-dev:/usr/local/es/elasticsearch-5.6.8$ cat config/elasticsearch.yml
# ======================== 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
cluster.name: td-es
#
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
#node.name: node-1
node.name: data1
node.master: false
#node.master: true
node.data: true
#
# 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.data: /mnt/local/data/es/data
# Path to log files:
#
#path.logs: /path/to/logs
path.logs: /mnt/local/data/es/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: 192.168.0.1
network.host: ip1
# Set a custom port for HTTP:
#
#http.port: 9200
http.port: 9200
transport.tcp.port: 9300
discovery.zen.ping_timeout: 60s

#discovery.zen.ping.unicast.hosts: ["ip1","ip2"]
#discovery.zen.minimum_master_nodes: 2
discovery.zen.ping.unicast.hosts: ["ip1:9301","ip2:9301","ip3:9301"]
discovery.zen.minimum_master_nodes: 2

#discovery.zen.ping.multicast.enabled: false
#head
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization,X-Requested-With,Content-Length,Content-Type

bootstrap.memory_lock: false
bootstrap.system_call_filter: false
#
xpack.security.enabled: false
#xpack.reporting.enabled: false
xpack.monitoring.enabled: false
#action.auto_create_index: .security,.monitoring*,.watches,.triggered_watches,.watcher-history*
#xpack.monitoring.elasticsearch.username: "elastic"
#xpack.monitoring.elasticsearch.password: "changeme"


#elsticsearch.username: "elastic"
#elasticsearch.password: "changeme"

#For more information, consult the network module documentation.
#
# --------------------------------- Discovery ----------------------------------
#
# Pass an initial list of hosts to perform discovery when new node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
#discovery.zen.ping.unicast.hosts: ["host1", "host2"]
#
# Prevent the "split brain" by configuring the majority of nodes (total number of master-eligible nodes / 2 + 1):
#
#discovery.zen.minimum_master_nodes: 3
#
# For more information, consult the zen discovery 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
indices.fielddata.cache.size: 20%

master1

es@spark-dev:/usr/local/es/elasticsearch-5.6.8_2$ cat config/elasticsearch.yml
# ======================== 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
cluster.name: td-es
#cluster.name: zzy-es
#
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
#node.name: node-1
node.name: master1
#node.master: false
node.master: true
node.data: false
#
# 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.data: /mnt/local/data/es/data2
# Path to log files:
#
#path.logs: /path/to/logs
path.logs: /mnt/local/data/es/logs2
#
# ----------------------------------- 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: 192.168.0.1
network.host: ip1
# Set a custom port for HTTP:
#
#http.port: 9200
http.port: 9201
#
transport.tcp.port: 9301
discovery.zen.ping_timeout: 60s

#discovery.zen.ping.unicast.hosts: ["ip1","ip2"]
#discovery.zen.minimum_master_nodes: 2
discovery.zen.ping.unicast.hosts: ["ip1","ip2","ip3"]
discovery.zen.minimum_master_nodes: 2

#head
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization,X-Requested-With,Content-Length,Content-Type


bootstrap.memory_lock: false
bootstrap.system_call_filter: false

xpack.security.enabled: false
#xpack.reporting.enabled: false
xpack.monitoring.enabled: false
#action.auto_create_index: .security,.monitoring*,.watches,.triggered_watches,.watcher-history*
#xpack.monitoring.elasticsearch.username: "elastic"
#xpack.monitoring.elasticsearch.password: "changeme"


# For more information, consult the network module documentation.
#
# --------------------------------- Discovery ----------------------------------
#
# Pass an initial list of hosts to perform discovery when new node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
#discovery.zen.ping.unicast.hosts: ["host1", "host2"]
#
# Prevent the "split brain" by configuring the majority of nodes (total number of master-eligible nodes / 2 + 1):
#
#discovery.zen.minimum_master_nodes: 3
#
# For more information, consult the zen discovery 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
indices.fielddata.cache.size: 20%

jvm配置

es@spark-dev:/usr/local/es/elasticsearch-5.6.8$ cat config/jvm.options
##JVM configuration

################################################################
## IMPORTANT: JVM heap size
################################################################
##
## You should always set the min and max JVM heap
## size to the same value. For example, to set
## the heap to 4 GB, set:
##
## -Xms4g
## -Xmx4g
##
## See https://www.elastic.co/guide/en/elasticsearch/reference/current/heap-size.html
## for more information
##
################################################################

# Xms represents the initial size of total heap space
# Xmx represents the maximum size of total heap space

-Xms32g
-Xmx32g
#-Xms4g
#-Xmx4g

################################################################
## Expert settings
################################################################
##
## All settings below this section are considered
## expert settings. Don't tamper with them unless
## you understand what you are doing
##
################################################################

## GC configuration
-XX:+UseConcMarkSweepGC
-XX:CMSInitiatingOccupancyFraction=75
-XX:+UseCMSInitiatingOccupancyOnly

## optimizations

# pre-touch memory pages used by the JVM during initialization
-XX:+AlwaysPreTouch

## basic

# force the server VM (remove on 32-bit client JVMs)
-server

# explicitly set the stack size (reduce to 320k on 32-bit client JVMs)
-Xss1m

# set to headless, just in case
-Djava.awt.headless=true

# ensure UTF-8 encoding by default (e.g. filenames)
-Dfile.encoding=UTF-8

# use our provided JNA always versus the system one
-Djna.nosys=true

# use old-style file permissions on JDK9
-Djdk.io.permissionsUseCanonicalPath=true

# flags to configure Netty
-Dio.netty.noUnsafe=true
-Dio.netty.noKeySetOptimization=true
-Dio.netty.recycler.maxCapacityPerThread=0

# log4j 2
-Dlog4j.shutdownHookEnabled=false
-Dlog4j2.disable.jmx=true
-Dlog4j.skipJansi=true

## heap dumps

# generate a heap dump when an allocation from the Java heap fails
# heap dumps are created in the working directory of the JVM
-XX:+HeapDumpOnOutOfMemoryError

# specify an alternative path for heap dumps
# ensure the directory exists and has sufficient space
#-XX:HeapDumpPath=${heap.dump.path}

## GC logging

#-XX:+PrintGCDetails
#-XX:+PrintGCTimeStamps
#-XX:+PrintGCDateStamps
#-XX:+PrintClassHistogram
#-XX:+PrintTenuringDistribution
#-XX:+PrintGCApplicationStoppedTime

# log GC status to a file with time stamps
# ensure the directory exists
#-Xloggc:${loggc}

# By default, the GC log file will not rotate.
# By uncommenting the lines below, the GC log file
# will be rotated every 128MB at most 32 times.
#-XX:+UseGCLogFileRotation
#-XX:NumberOfGCLogFiles=32
#-XX:GCLogFileSize=128M

# Elasticsearch 5.0.0 will throw an exception on unquoted field names in JSON.
# If documents were already indexed with unquoted fields in a previous version
# of Elasticsearch, some operations may throw errors.
#
# WARNING: This option will be removed in Elasticsearch 6.0.0 and is provided
# only for migration purposes.
#-Delasticsearch.json.allow_unquoted_field_names=true

data2

es@es3:/usr/local/es/elasticsearch-5.6.8$ cat config/elasticsearch.yml
# ======================== 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
cluster.name: td-es
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
#node.name: node-1
node.name: data2
node.master: false
node.data: true
# 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.data: /mnt/local/data/es/data
# Path to log files:
#
#path.logs: /path/to/logs
path.logs: /mnt/local/data/es/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: 192.168.0.1
network.host: ip2
#
# Set a custom port for HTTP:
http.port: 9200
transport.tcp.port: 9300
discovery.zen.ping_timeout: 60s

#discovery.zen.ping.unicast.hosts: ["ip1","ip2"]
#discovery.zen.minimum_master_nodes: 2
discovery.zen.ping.unicast.hosts: ["ip1:9301","ip2:9301","ip3:9301"]
discovery.zen.minimum_master_nodes: 2

#head
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization,X-Requested-With,Content-Length,Content-Type

bootstrap.memory_lock: false
bootstrap.system_call_filter: false

#
xpack.security.enabled: false
#xpack.reporting.enabled: false
xpack.monitoring.enabled: false

#xpack.monitoring.exporters.auth.username: "elastic"
#xpack.monitoring.exporters.auth.password: "changeme"
#xpack.security.audit.enabled: true

#action.auto_create_index: .security,.monitoring*,.watches,.triggered_watches,.watcher-history*

#elasticsearch.username: "elastic"
#elasticsearch.password: "changeme"
# 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 new node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
#discovery.zen.ping.unicast.hosts: ["host1", "host2"]
#
# Prevent the "split brain" by configuring the majority of nodes (total number of master-eligible nodes / 2 + 1):
#
#discovery.zen.minimum_master_nodes: 3
#
# For more information, consult the zen discovery 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
indices.fielddata.cache.size: 20%

master2

es@es3:/usr/local/es/elasticsearch-5.6.8_2$ cat config/elasticsearch.yml
# ======================== 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
cluster.name: td-es
#cluster.name: zzy-es
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
#node.name: node-1
node.name: master2
node.master: true
node.data: false
# 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.data: /mnt/local/data/es/data2
# Path to log files:
#
#path.logs: /path/to/logs
path.logs: /mnt/local/data/es/logs2
#
# ----------------------------------- 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: 192.168.0.1
network.host: ip2
#
# Set a custom port for HTTP:
http.port: 9201
transport.tcp.port: 9301
discovery.zen.ping_timeout: 60s

#discovery.zen.ping.unicast.hosts: ["ip1","ip2"]
#discovery.zen.minimum_master_nodes: 2
discovery.zen.ping.unicast.hosts: ["ip1","ip2","ip3"]
discovery.zen.minimum_master_nodes: 2

#head
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization,X-Requested-With,Content-Length,Content-Type

bootstrap.memory_lock: false
bootstrap.system_call_filter: false

#
xpack.security.enabled: false
#xpack.reporting.enabled: false
xpack.monitoring.enabled: false

#xpack.monitoring.exporters.auth.username: "elastic"
#xpack.monitoring.exporters.auth.password: "changeme"
#xpack.security.audit.enabled: true

#action.auto_create_index: .security,.monitoring*,.watches,.triggered_watches,.watcher-history*

#elasticsearch.username: "elastic"
#elasticsearch.password: "changeme"
# 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 new node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
#discovery.zen.ping.unicast.hosts: ["host1", "host2"]
#
# Prevent the "split brain" by configuring the majority of nodes (total number of master-eligible nodes / 2 + 1):
#
#discovery.zen.minimum_master_nodes: 3
#
# For more information, consult the zen discovery 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
indices.fielddata.cache.size: 20%

data3

es@es4:/usr/local/es/elasticsearch-5.6.8$ cat config/elasticsearch.yml
# ======================== 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
cluster.name: td-es
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
#node.name: node-1
node.name: data3
node.master: false
node.data: true
# 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.data: /mnt/local/data/es/data
# Path to log files:
#
#path.logs: /path/to/logs
path.logs: /mnt/local/data/es/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: 192.168.0.1
#network.host: 0.0.0.0
network.host: ip3
#
# Set a custom port for HTTP:
http.port: 9200
transport.tcp.port: 9300
discovery.zen.ping_timeout: 60s

#discovery.zen.ping.unicast.hosts: ["ip1","ip2"]
#discovery.zen.minimum_master_nodes: 2
discovery.zen.ping.unicast.hosts: ["ip1:9301","ip2:9301","ip3:9301"]
discovery.zen.minimum_master_nodes: 2

#head
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization,X-Requested-With,Content-Length,Content-Type

bootstrap.memory_lock: false
bootstrap.system_call_filter: false
#
xpack.security.enabled: false
#xpack.reporting.enabled: false
#xpack.monitoring.enabled: false

#xpack.monitoring.exporters.auth.username: "elastic"
#xpack.monitoring.exporters.auth.password: "changeme"
#xpack.security.audit.enabled: true

#action.auto_create_index: .security,.monitoring*,.watches,.triggered_watches,.watcher-history*

#elasticsearch.username: "elastic"
#elasticsearch.password: "changeme"
# 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 new node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
#discovery.zen.ping.unicast.hosts: ["host1", "host2"]
#
# Prevent the "split brain" by configuring the majority of nodes (total number of master-eligible nodes / 2 + 1):
#
#discovery.zen.minimum_master_nodes: 3
#
# For more information, consult the zen discovery 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
indices.fielddata.cache.size: 20%

master3

es@es4:/usr/local/es/elasticsearch-5.6.8_2$ cat config/elasticsearch.yml
# ======================== 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
cluster.name: td-es
#cluster.name: zzy-es
# ------------------------------------ Node ------------------------------------
#
# Use a descriptive name for the node:
#
#node.name: node-1
node.name: master3
node.master: true
node.data: false
# 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.data: /mnt/local/data/es/data2
# Path to log files:
#
#path.logs: /path/to/logs
path.logs: /mnt/local/data/es/logs2
#
# ----------------------------------- 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: 192.168.0.1
#network.host: 0.0.0.0
network.host: ip1
#
# Set a custom port for HTTP:
http.port: 9201
transport.tcp.port: 9301
discovery.zen.ping_timeout: 60s

#discovery.zen.ping.unicast.hosts: ["ip1","ip2"]
#discovery.zen.minimum_master_nodes: 2
discovery.zen.ping.unicast.hosts: ["ip1","ip2","ip3"]
discovery.zen.minimum_master_nodes: 2

#head
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization,X-Requested-With,Content-Length,Content-Type

bootstrap.memory_lock: false
bootstrap.system_call_filter: false
#
xpack.security.enabled: false
#xpack.reporting.enabled: false
xpack.monitoring.enabled: false

#xpack.monitoring.exporters.auth.username: "elastic"
#xpack.monitoring.exporters.auth.password: "changeme"
#xpack.security.audit.enabled: true

#action.auto_create_index: .security,.monitoring*,.watches,.triggered_watches,.watcher-history*

#elasticsearch.username: "elastic"
#elasticsearch.password: "changeme"
# 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 new node is started:
# The default list of hosts is ["127.0.0.1", "[::1]"]
#
#discovery.zen.ping.unicast.hosts: ["host1", "host2"]
#
# Prevent the "split brain" by configuring the majority of nodes (total number of master-eligible nodes / 2 + 1):
#
#discovery.zen.minimum_master_nodes: 3
#
# For more information, consult the zen discovery 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
indices.fielddata.cache.size: 20%

ES初学中，欢迎一起学习交流！

参考：

https://blog.csdn.net/lu_wei_wei/article/details/51263153

https://blog.csdn.net/u013673976/article/details/73650889

https://blog.csdn.net/shudaqi2010/article/details/71711610

https://nickcanzoneri.com/elasticsearch-settings/