OpenSearch installation

Installation procedure

There are several ways to install OpenSearch, explained step by step in the official documentation.

Configuration

To configure your OpenSearch instance, edit the ${OPENSEARCH_HOME}/config/opensearch.yml file as follows:

• To define the name of the OpenSearch cluster, uncomment the cluster.name property and change its value (eg: flower-es-dev)
• In the case of an OpenSearch cluster, uncomment the node.name property and change its value to that of your choice (e.g. node-1)
• Add the action.auto_create_index: false property
• If several OpenSearch nodes are deployed on the same computer, you need to change the value of the http.port property
• To access OpenSearch from a remote server, you need to uncomment the network.host property and set one of the following values:
  • 0.0.0.0
  • DNS name
  • IP address

Security

OpenSearch internal users are defined in the ${OPENSEARCH_HOME}/plugins/opensearch-security/securityconfig/internal_users.yml file.

To change a user’s password:

• run command: ${OPENSEARCH_HOME}/plugins/opensearch-security/tools/hash.sh -p <new_password>
• Replace the password hash in the ${OPENSEARCH_HOME}/plugins/opensearch-security/securityconfig/internal_users.yml file for the desired user.
• in order for the changes to take effect, run the ${OPENSEARCH_HOME}/plugins/opensearch-security/tools/securityadmin.sh script

For more information on securing an OpenSearch instance, official documentation is available here.

Start

Manuel

Finally, start OpenSearch by going to the ${OPENSEARCH_HOME}/bin folder and running the opensearch script.

Service

To install OpenSearch as a systemd service, the following file must be created in the /etc/systemd/system directory as follows:

[Unit]
Description=opensearch
Wants=network-online.target
After=network-online.target

[Service]
RuntimeDirectory=opensearch
PrivateTmp=true

WorkingDirectory=${OPENSEARCH_HOME}

User=${OPENSEARCH_USER}
Group=${OPENSEARCH_USER}

ExecStart=${OPENSEARCH_HOME}/bin/opensearch -p ${OPENSEARCH_HOME}/opensearch.pid -q

StandardOutput=journal
StandardError=inherit

# Specifies the maximum file descriptor number that can be opened by this process
LimitNOFILE=65536

# Specifies the memory lock settings
LimitMEMLOCK=infinity

# Specifies the maximum number of processes
LimitNPROC=4096

# Specifies the maximum size of virtual memory
LimitAS=infinity

# Specifies the maximum file size
LimitFSIZE=infinity

# Disable timeout logic and wait until process is stopped
TimeoutStopSec=0

# SIGTERM signal is used to stop the Java process
KillSignal=SIGTERM

# Send the signal only to the JVM rather than its control group
KillMode=process

# Java process is never killed
SendSIGKILL=no

# When a JVM receives a SIGTERM signal it exits with code 143
SuccessExitStatus=143

[Install]
WantedBy=multi-user.target

To have the service started automatically by systemd, run the following commands:

  systemctl enable opensearch.service

Validation

To check that OpenSearch is working properly, go to http://localhost:9200/.