Install Elasticsearch 7 on Ubuntu for Magento 2.3

To install Elasticsearch, add the key

wget -qO - https://artifacts.elastic.co/GPG-KEY-elasticsearch | sudo gpg --dearmor -o /usr/share/keyrings/elasticsearch-keyring.gpg

Install apt-transport-https

sudo apt-get install apt-transport-https

Add apt repository

echo "deb [signed-by=/usr/share/keyrings/elasticsearch-keyring.gpg] https://artifacts.elastic.co/packages/7.x/apt stable main" | sudo tee /etc/apt/sources.list.d/elastic-7.x.list

install elasticsearch with apt

apt-get update
apt-get install elasticsearch

Set elasticsearch to start on boot

systemctl daemon-reload
systemctl enable elasticsearch

Elasticsearch can be started and stopped as follows:

systemctl start elasticsearch
systemctl stop elasticsearch

Verify Elasticsearch is running with

systemctl status elasticsearch

or with

curl localhost:9200

if it fails to start, you can debug it with

journalctl --unit elasticsearch

Official install instructions at

https://www.elastic.co/guide/en/elasticsearch/reference/8.3/deb.html