How to Install Magento 2 Elasticsearch in linux server

Elasticsearch is an open-source distributed full-text search engine with an HTTP web interface and schema-free JSON documents. Elasticsearch is a quick and advanced search in product catalog. From Magento version 2.4 it is mandatory to setup elasticsearch for product catalog solution. For the Magento 2.4 version, you need to use the elasticsearch version 7.6+.

Elasticsearch is Developed in java.

Elasticsearch Installation for Magento 2.4 steps in Ubuntu

1. Install Java Development Kit
2. Install elasticsearch
3. Configure and start elasticsearch

Install Java Development Kit

Navigate to user’s home directory and then first step to updating repository by below command

sudo apt-get update

Install JDK

To install java Development kit by 

sudo apt-get install openjdk-8-jdk -y

Confirmation of installation of jdk

Run java -version   (note keep small j in java)

java -version

Example output as below:

Installing Elasticsearch

Install dependency

sudo apt install apt-transport-https ca-certificates wget

Import repository GPG key:

wget -qO - https://artifacts.elastic.co/GPG-KEY-elasticsearch | sudo apt-key add -

Add elasticsearch repository to the system

sudo sh -c 'echo "deb https://artifacts.elastic.co/packages/7.x/apt stable main" > /etc/apt/sources.list.d/elastic-7.x.list'

Replace 7.x with necessary elasticsearch version, keep as it is if you are installing for magento2.4

After importing repository to system update system and then install elasticsearch

sudo apt update

sudo apt install elasticsearch

Configure and start Elasticsearch

Elasticsearch is installed and now we need to configure it and need to start it.

We have to change the network host 

Open elasticsearch config file using below command

sudo nano /etc/elasticsearch/elasticsearch.yml

Update Network host:

Change network.host value to “localhost”. Default value is 192.168.X.X  which you can remove also don't forget to remove preceding ‘#’ (comment).

Another configuration you can do but optional to do

Update cluster name;

Cluster.name  write any relevant cluster name and remove preceding ‘#’

Update Node Name:

You can update node.name to a relevant name like “Magento 2_4” .

Additionally you can change the port of elasticsearch but by default it is 9200.

Http.port to anyport you want to use.

Also note that you need to enable the port inbound rule in the security group if you are using AWS server.

Save file but ctrl+x to exit, and press Y to save and press 'enter' to confirm.

Now start elasticsearch by below command

sudo systemctl start elasticsearch

To restart elasticsearch

sudo systemctl restart elasticsearch

Test elasticsearch

curl -X GET 'http://localhost:9200'

You will see result similar to below one:

If you are getting error to enable elasticsearch then you may need to change

If there is error due to memory Then you need to do below configuration

Elasticsearch is JVM application, so elasticsearch uses memory which are devoted to jvm.

Elasticsearch mostly depend on heapmemory which can be manually configurable in jvm options by -xms and -xmx value.

-Xms = initial size of heap space.

-Xmx = maximum size of heap space.

Open jvm.option file by below command

sudo nano /etc/elasticsearch/jvm.options

Allow no more than 25% of physical memory to heap spacie. 

Example if you are running application in 1GB RAM then set below configuration

-Xms128m

-Xmx128m

Or 

-Xms256m

-Xmx256m

Save file but ctrl+x to exit, and press Y to save and press 'enter' to confirm.

Now again restart elasticsearch by below command

sudo systemctl restart elasticsearch

Test Magento 2 elasticsearch

curl -X GET http://localhost:9200

You will ses similar result as below:

Yay! Your Magento2 Elasticsearch is ready now!