Install ElasticSearch on linux

ElasticSearch is installed on linux

ES installation version: 6.3.0
Linux system: centos7
ik analysis plug-in: 6.3.0
kibana version: 6.3.0
virtual machine JDK1.8

Create a new user leyou (you can start any name)

Reason: For security reasons, elasticsearch is not allowed to run as root by default.
Create user:

useradd leyou

set password:

passwd leyou

Switch user:

su - leyou

Upload the installation package and unzip

We upload the installation package to: /home/leyou directory
Unzip:

tar -zxvf elasticsearch-6.2.4.tar.gz

We rename the directory:

mv elasticsearch-6.3.0/ elasticsearch

Enter and view the directory structure:

Change setting

We enter the config directory: cd config
there are two configuration files that need to be modified:

1. jvm.options

Elasticsearch is based on Lucene, and the bottom layer of Lucene is implemented in Java, so we need to configure the jvm parameters.

Edit jvm.options:

vim jvm.options

The default configuration is as follows:

-Xms1g
-Xmx1g

The memory takes up too much, let's reduce it:

-Xms512m
-Xmx512m

2. elasticsearch.yml

vim elasticsearch.yml

• Modify the data and log directory:

path.data: /home/leyou/elasticsearch/data # 数据目录位置
path.logs: /home/leyou/elasticsearch/logs # 日志目录位置

We modified the data and logs directories to point to the elasticsearch installation directory. But these two directories do not exist, so we need to create them.
Enter the root directory of elasticsearch, the logs directory already exists, so just create the data directory, and then create:

mkdir data
mkdir logs

Modify the bound ip:

vim elasticsearch.yml
network.host: 0.0.0.0 # Bind to 0.0.0.0, allowing any ip to access

At present, we are doing a stand-alone installation. If you want to do a cluster, you only need to add other node information in this configuration file.
Other configurable information of elasticsearch.yml:

Attribute name	Description
cluster.name	Configure the cluster name of elasticsearch. The default is elasticsearch. It is recommended to modify it to a meaningful name.
node.name	Node name, es will randomly assign a name by default, it is recommended to assign a meaningful name to facilitate management
path.conf	Set the storage path of the configuration file. The tar or zip package is installed in the config folder under the es root directory by default, and the rpm installation is in /etc/elasticsearch by default.
path.data	Set the storage path of index data. The default is the data folder under the es root directory. Multiple storage paths can be set, separated by commas.
path.logs	Set the storage path of the log file, the default is the logs folder under the es root directory
path.plugins	Set the storage path of the plugin, the default is the plugins folder under the es root directory
bootstrap.memory_lock	Set to true to lock the memory used by ES and avoid memory swap
network.host	Set bind_host and publish_host, set to 0.0.0.0 to allow external network access
http.port	Set the http port for external services, the default is 9200.
transport.tcp.port	Communication port between cluster nodes
discovery.zen.ping.timeout	Set the time for ES to automatically discover the node connection timeout, the default is 3 seconds, if the network delay is high, it can be set larger
discovery.zen.minimum_master_nodes	The minimum value of the number of master nodes, the formula for this value is: (master_eligible_nodes / 2) + 1, for example: if there are 3 master nodes that meet the requirements, then it should be set to 2 here

run

Enter the elasticsearch/bin directory, you can see the following executable file:

Then enter the command:

./elasticsearch

Error 1: The core is too low

The centos6 used has a linux kernel version of 2.6. The Elasticsearch plugin requires at least version 3.5. But it doesn't matter, we can disable this plugin.

Modify the elasticsearch.yml file and add the following configuration at the bottom:

bootstrap.system_call_filter: false

Then restart

Error 2: Insufficient file permissions

Started again, another error occurred:

[1]: max file descriptors [4096] for elasticsearch process likely too low, increase to at least [65536]

We use the leyou user instead of root, so the file permissions are insufficient.

First log in as root user.

Then modify the configuration file:

vim /etc/security/limits.conf

Add the following content:

• soft nofile 65536
• hard nofile 131072
• soft nproc 4096
• hard nproc 4096

Mistake 3: Not enough threads

In the error report, there is another line:

[1]: max number of threads [1024] for user [leyou] is too low, increase to at least [4096]

This is not enough threads.
Continue to modify the configuration:

vim /etc/security/limits.d/90-nproc.conf

Modify the following content:

• soft nproc 1024

To:

• soft nproc 4096

Error 4: Process virtual memory

[3]: max virtual memory areas vm.max_map_count [65530] likely too low, increase to at least [262144]

vm.max_map_count: Limit the number of VMA (virtual memory area) a process can have, continue to modify the configuration file,:

vim /etc/sysctl.conf

Add the following content:

vm.max_map_count=655360

Then execute the command:

sysctl -p

My mistake is as follows:

Then modify it according to the above scheme. Note: Only the root user can modify those files

Restart the terminal window

After all errors are corrected, you must restart your Xshell terminal, otherwise the configuration will be invalid.

start up

Start ES as the leyou user at startup

Visit the ES of the virtual machine in the browser in the window, turn off the firewall, and the Es is installed

Kibana

Because Kibana depends on node, our virtual machine does not have node installed, but it was installed in the window. So we choose to use kibana under the window.
The latest version is consistent with elasticsearch, also 6.3.0, unzip to a specific directory to
configure and run

Enter the config directory under the installation directory and modify the kibana.yml file:
modify the address of the elasticsearch server:

elasticsearch.url: “http://192.168.1.181:9200”

Enter the bin directory under the installation directory:

double-click to run:

It is found that the listening port of kibana is 5601.
We visit: http://localhost:5601

Select the DevTools menu on the left to enter the console page:
on the right side of the page, we can enter a request and access Elasticsearch.

Install ik tokenizer

installation

Upload the elasticsearch-analysis-ik-6.3.0.zip package and unzip it to the plugins directory of the Elasticsearch directory:
use the unzip command to unzip:

unzip elasticsearch-analysis-ik-6.3.0.zip -d i-analyzer

Then restart elasticsearch:

test

Enter the following request in the kibana console:

POST _analyze
{
  "analyzer": "ik_max_word",
  "text":     "我是中国人"
}