# Unnecessary multi-AZ configuration for non-production RDS instances

Canonical: https://www.pointfive.co/efficiency-hub/inefficiencies/unnecessary-multi-az-configuration-for-non-production-rds-instances

RDS Multi-AZ deployments are designed for production-grade fault tolerance.

By: Swapna Samuel

Updated: 2026-09-28

[Cloud Efficiency Hub](https://www.pointfive.co/efficiency-hub) 

# Unnecessary Multi-AZ Configuration for Non-Production RDS Instances

The short version

RDS Multi-AZ deployments are designed for production-grade fault tolerance.

[Swapna Samuel](https://www.linkedin.com/in/swapna-samuel-792745111/)

Head, Central Cloud FinOps & Clarity Business Management @ BMO

AWS service

[AWS RDS](https://www.pointfive.co/efficiency-hub/cloud-services/aws-rds)

Category

[Databases](https://www.pointfive.co/efficiency-hub/service-category/databases)

Reference

CER-0210

Type

Inefficient Configuration

## Explanation

Why the waste happens and who it affects.

In non-production environments, a Multi-AZ DB instance deployment roughly doubles the cost of database instances and storage, and a Multi-AZ DB cluster runs three DB instances (one writer and two readers), with little added value. Unless explicitly required for high-availability testing, Multi-AZ in dev, staging, or test environments typically results in avoidable expense.

## Billing model

The pricing dimensions that drive this cost.

RDS Multi-AZ instance deployments incur compute and storage charges for both the primary and the standby. Data transferred between Availability Zones for Multi-AZ replication is free.

## How to detect

How to find it in your estate.

Identify RDS instances in non-production accounts or environments with Multi-AZ enabled Use environment tags or naming conventions to distinguish staging and development workloads Evaluate instance-level metrics to assess whether failover capabilities are actively used or needed Check for duplicated storage and compute resources across Availability Zones

## How to fix

How to remove the waste.

Modify RDS instances in non-production environments to use single-AZ deployment Update provisioning templates and IaC modules to default to single-AZ for non-prod Create safeguards to prevent Multi-AZ deployments in dev/test unless explicitly approved

## Documentation

Vendor references for pricing and configuration.

- [Configuring and managing a Multi-AZ deployment for Amazon RDS  docs.aws.amazon.com](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Concepts.MultiAZ.html)

- [Multi-AZ DB cluster deployments for Amazon RDS  docs.aws.amazon.com](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/multi-az-db-clusters-concepts.html)

- [Amazon RDS Pricing  aws.amazon.com](https://aws.amazon.com/rds/pricing/)

## Related inefficiencies

[Browse the library](https://www.pointfive.co/efficiency-hub)

- AWS RDS  CER-0322

### [Non-Production RDS SQL Server Using Standard or Enterprise Edition Instead of Developer Edition](https://www.pointfive.co/efficiency-hub/inefficiencies/non-production-rds-sql-server-using-standard-or-enterprise-edition-instead-of-developer-edition)

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### [Suboptimal RDS Instance Storage Type](https://www.pointfive.co/efficiency-hub/inefficiencies/suboptimal-rds-instance-storage-type)

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Source: the public page above. Product screenshots and illustrative interfaces are examples, not live customer data.