# Overview

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Exoscale **Managed PostgreSQL** delivers a fully managed, high-availability deployment of the popular open-source database engine.  The service is aimed at teams that need rock-solid ACID compliance, automated operations, and predictable performance without managing infrastructure themselves.


## Terminology
Service
: A running PostgreSQL cluster managed by Exoscale DBaaS

Plan
: A size / redundancy tier (`hobbyist-1`, `startup-4`, `business-32`,
  `premium-9x-16`, …)

Fork
: A point-in-time clone of an existing service (used for upgrades, DR tests,
  etc.)

Read Replica
: A replica created through the DBaaS “read replica” integration

pgBouncer
: Built-in connection pooler that fronts every service for higher connection
  density


## Features
Managed Cluster Lifecycle
: automated provisioning, patching and minor-version upgrades.

Automatic Daily Backups
: with user-defined retention and point-in-time recovery (PITR) on Business
  & Premium plans.

Vertical & Horizontal Scaling
: change plan size or add read replicas without downtime.

Connection Pooling
: pgBouncer is pre-configured for each service, reducing idle connection load.

High SLA
: 99.95 % on Startup, 99.99 % on Business / Premium plans; no SLA on Hobbyist.

CLI & API First
: every feature exposed via `exo dbaas …`; the Portal currently covers common
  workflows.