# Overview

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Managed __OpenSearch__ on Exoscale is a fully-managed, open-source search-and-analytics engine delivered as Database-as-a-Service (DBaaS). Built on the community-driven fork of Elasticsearch 7.10.2, it provides a familiar API, OpenSearch Dashboards, and enterprise-grade operational automation—so you can focus on ingesting, searching, and visualising data instead of running clusters.


## Terminology
Service
: A managed OpenSearch deployment, isolated per customer.

Cluster
: One or more OpenSearch nodes backing a service.

Node
: A virtual machine that stores data and executes queries.

Index
: A logical collection of JSON documents.

Shard / Replica
: Primary or copy of a shard that distributes an index across nodes for
  scalability and resilience.

Plan
: Preset resources & redundancy level (hobbyist, startup, business, premium).

Dashboard
: The built-in OpenSearch Dashboards UI for visualisation and management.


## Features
Managed lifecycle
: automated provisioning, rolling upgrades, in-place re-sizing, and health
  monitoring.

High availability options
: multi-node business / premium plans with adjustable `number_of_replicas`.
  Automatic safeguards ensure the replica count always fits the cluster size.

OpenSearch Dashboards
: one-click access for ad-hoc queries and visualisations.

Security by default
: TLS-encrypted endpoints, IP filtering, and service-level isolation.

Automated backups
: daily encrypted snapshots retained per-plan.

Horizontal & vertical scaling
: upgrade RAM/CPU or add nodes with zero-downtime operations via CLI/API.

> [!NOTE]- _OpenSearch vs Elasticsearch_
> OpenSearch is an open-source fork of the original Elasticsearch project. When Elastic NV adopted the 
> Server Side Public License (SSPL) in 2021, the licence prevented Exoscale from offering Elasticsearch 
> as a service. The community—including our DBaaS partner [Aiven](https://aiven.io)—responded by forking 
> the last Apache-licensed versions (7.10.2) of Elasticsearch and Kibana, creating __OpenSearch__ and __OpenSearch Dashboards__.