OpenSearch Cluster

The OpenSearch Cluster is a community-driven, open-source search engine. It is most suitable for application search or log analytics cases, as it enables people to easily search, aggregate, view, and analyze data. OpenSearch provides a secure, high-quality search and analytics suite that can be easily modified and extended with additional functionality.

OpenSearch is derived from Apache 2.0 licensed Elasticsearch 7.10.2, allowing the product to be freely used, modified, extended, monetized, and resold.

This guide provides information on:

OpenSearch Cluster Components Overview

Jelastic PaaS provides OpenSearch Cluster using three certified stacks that are united into a single auto-clustering solution:

  • OpenSearch - a community-driven, open-source search engine that provides a distributed, multitenant-capable full-text search
  • OpenSearch Dashboards (optional) - visualization for data stored inside the OpenSearch nodes (derived from Kibana 7.10.2)
  • Logstash (optional) - data processing
Tip: Additionally, the Beats add-on can be installed for single-purpose data shippers that send data from the client nodes to Logstash or OpenSearch.

In such a solution, data is gathered on client nodes by Beats Data Shippers, sent to Logstash (which transforms it the needed way), and stored in OpenSearch. OpenSearch Dashboard is the supplementary visualization tool.

OpenSearch

The OpenSearch stack is the core and the only mandatory component of the cluster. It is initialized in the cluster mode even when a single node is created, which makes horizontal scaling easier, faster, and safer.

After being created, the OpenSearch node is available on port 9200 for internal communication between nodes of the environment and port 4848 for external services through the shared load balancer. The HTTP basic auth is used in both cases (password can be reset using the Reset Password button).

OpenSearch reset password

The OpenSearch stack benefits from all the functionality available for other certified templates - dashboard file manager, Web SSH, dashboard log viewer, etc.

Also, Jelastic’s redeploy functionality provides a simple update process. However, only redeployment to the same or newer version is allowed - a downgrade is restricted.

OpenSearch Dashboards

The OpenSearch node is available via browser, but it only shows the JSON with API response (required for API calls). The main tool for visualizing the data is OpenSearch Dashboards (replacement on Kibana). All the interconnection configurations are done automatically - the solution is ready for usage out-of-the-box and does not need any manual configuration. Access is available by the same credentials as for the OpenSearch node.

login OpenSearch Dashboards

After logging in, the OpenSearch Dashboards interface is displayed. The dashboard provides UI for convenient interaction with the OpenSearch API and editing your data (after creating the index pattern).

OpenSearch Dashboard UI

Note: The OpenSearch Dashboards is not a separate stack and cannot be created separately from OpenSearch. Also, it is limited to one node as scaling provides no additional benefits.

All the regular functionality of certified templates (Jelastic dashboard file manager, Web SSH, firewall, logs) is also available for this node.

Logstash

Logstash is a data processor component of the OpenSearch cluster that is automatically configured by the platform. Below, you can see an example of default auto-configuration for /etc/logstash/conf.d/logstash-sample.conf:

Logstash configs

The input for Beats is assigned on port 5044, and the OpenSearch output is specified by setting the hosts, username, and password for interconnection. Plugins for other types of inputs can be installed by the logstash-plugin tool, and configs can be added to the same file (with another port).

Note: The Logstash is not a separate stack and cannot be created separately from OpenSearch. You can add as many Logstash nodes as needed - scaling is in stateful mode to provide initial configs. However, each node can be reconfigured for different data transformations.

Beats Add-On

Beats is a free and open platform for single-purpose data shippers. They send data from the client nodes to Logstash or OpenSearch.

You can install Beats add-on on any node (except alpine-based ones) created inside the Jelastic PaaS and specify the credentials to connect to the OpenSearch cluster or custom Docker with the ElasticSearch instance. Two versions of the add-on are available:

Note: For direct connection, you need to add the following line to the OpenSearch config and restart node:

1
compatibility.override_main_response_version: true
  • latest - to ship data to OpenSearch through Logstash

Beats add-on

During installation, you need to provide the following data:

  • Installed agents - choose the required Beats types:
    • Filebeat - forwards and centralizes logs and files. Pre-sets are already available for many certified nodes: Apache (all), NGINX (all), HAProxy, Redis, Postgres, MySQL, MariaDB, Percona, MongoDB. Tomcat/TomEE requires special configurations.
    • Metricbeat - collects metrics from your systems and services.
    • Journalbeat - forwards and centralizes log data from systemd journals. Installed as an agent on your servers, Journalbeat monitors the journal locations that you specify, collects log events, and forwards them to OpenSearch or Logstash.
    • Packetbeat - monitors your network traffic to ensure a high level of performance and security. Packetbeat is a lightweight network packet analyzer.
    • Heartbeat - monitors services for their availability with active probing. It checks response time and if the given URLs are alive, then ships this information to other stacks for further analysis.
  • OpenSearch Host (optional) - enter the OpenSearch (or Elasticsearch) host, login, and password (API key)
Note: Either the login-password or the API key can be used at once (not both). If the login and password are specified, the API key will not be inserted into the agent’s configuration file (and will not be used as a result).
  • OpenSearch Dashboards Host (optional) - enter the OpenSearch Dashboards host (may be needed for visualization purposes)
  • Logstash Host (optional) - enter the Logstash host (if interconnection is done through the Logstash)
Note: Simultaneously sending data to OpenSearch and Logstash outputs is not supported - only one output can be used at once. If you want to pass the data through the LogStash - please specify only the LogStash host and port (the OpenSearch host and credentials data is not needed).
  • Beats OSS version - choose the desired version of the agent
  • Environment - choose the target environment
  • Nodes - choose either All Nodes or Specific Nodes

These settings can also be edited for the already installed add-on using the Configure button:

configure Beats add-on

OpenSearch Cluster Installation

The OpenSearch Cluster creation at the Jelastic PaaS is a straightforward and fully automated process that can be performed directly from the topology wizard.

Select the OpenSearch stack at the NoSQL database section.

OpenSearch topology wizard

The stack is automatically configured as a cluster due to the auto-clustering feature. Also, you have additional options to add the OpenSearch Dashboards and Logstash components.

OpenSearch vs Elasticsearch Performance

The OpenSearch project was forked from the last ElasticSearch release under the Apache 2.0 license and is almost the same in functionality. The API is completely the same.

Below, we are sharing the results of a performance test on two Magento environments with the same topology:

  • Magento with Elasticsearch

ElasticSearch statistics

  • Magento with OpenSearch

OpenSearch statistics

As you can see, OpenSearch provides the same functionality and performance as Elasticsearch and can be used as its full-fledged replacement.

What’s next?