Elasticsearch

- Check if Java already installerd:

java -version

- Install OpenJDK

sudo apt install default-jre

- Verify installed JDK version

javac -version

- Setting the JAVA_HOME Environment Variable

sudo update-alternatives --config java

sudo vi /etc/environment

/etc/environment

...
JAVA_HOME="/usr/lib/jvm/java-11-openjdk-amd64"
ES_JAVA_HOME="/usr/lib/jvm/java-11-openjdk-amd64"

source /etc/environment

echo $JAVA_HOME

sudo apt install wget

curl -fsSL https://artifacts.elastic.co/GPG-KEY-elasticsearch |sudo gpg --dearmor -o /usr/share/keyrings/elastic.gpg

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

sudo apt update

sudo apt install elasticsearch

sudo vi /etc/elasticsearch/elasticsearch.yml

/etc/elasticsearch/elasticsearch.yml

...
# ---------------------------------- Network -----------------------------------
#
# By default Elasticsearch is only accessible on localhost. Set a different
# address here to expose this node on the network:
#
network.host: localhost
...