Ensure RDS instances have Multi-AZ enabled in Production


Enabling Multi-AZ for RDS Aurora clusters ensures high availability and automatic failover support. When Multi-AZ is enabled, AWS automatically sets up a synchronous database standby replica on a dedicated hardware in a different datacenter (known as an Availability Zone). In the event of a failure such as an Availability Zone outage, internal hardware or network outage, software failure, or planned interruptions such as software patching or changing the RDS cluster type, AWS RDS will automatically switch from the primary cluster to the available standby replica. To ensure high availability and automatic failover support for your RDS Aurora clusters, it is recommended to enable Multi-AZ deployment configurations. This will allow AWS to fully manage the standby replica, ensuring that your database remains available and functioning properly even in the event of a failure.


Enabling Multi-AZ (Availability Zones) for your RDS (Relational Database Service) instances in production is essential to improve availability, durability, and disaster recovery. Multi-AZ configuration automatically replicates the primary database to a standby database in a different Availability Zone, ensuring that if the primary database fails, the standby database can take over without data loss or downtime. Here are the remediation steps to ensure RDS instances have Multi-AZ enabled in production:

  1. Identify the RDS instances that are not configured for Multi-AZ. You can use the AWS Management Console or AWS CLI to identify the RDS instances that are not Multi-AZ enabled.
  2. Evaluate the impact of enabling Multi-AZ on each RDS instance. Enabling Multi-AZ may require additional resources, which could result in increased costs. Therefore, it's crucial to assess the potential impact on each RDS instance and determine if the benefits of Multi-AZ outweigh the costs.
  3. Take a snapshot of each RDS instance before enabling Multi-AZ. Taking a snapshot ensures that you have a backup of your data before making any changes.
  4. Enable Multi-AZ for each RDS instance using the AWS Management Console or AWS CLI. The process of enabling Multi-AZ involves modifying the RDS instance's configuration to replicate the primary database to a standby database in a different Availability Zone.
  5. Monitor the RDS instances after enabling Multi-AZ. It's essential to monitor the RDS instances to ensure that they are functioning correctly and to detect any issues that may arise.
  6. Test the failover process. Once Multi-AZ is enabled, you should test the failover process to ensure that it works correctly. You can simulate a failover by rebooting the primary instance or disconnecting it from the network.
  7. Review the AWS documentation and best practices for Multi-AZ. AWS provides extensive documentation and best practices for configuring Multi-AZ, which you should review to ensure that you are using Multi-AZ correctly.

By following these steps, you can ensure that your RDS instances have Multi-AZ enabled, which can improve their availability, durability, and disaster recovery capabilities.

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Note: Remediation steps provided by Lightlytics are meant to be suggestions and guidelines only. It is crucial to thoroughly verify and test any remediation steps before applying them to production environments. Each organization's infrastructure and security needs may differ, and blindly applying suggested remediation steps without proper testing could potentially cause unforeseen issues or vulnerabilities. Therefore, it is strongly recommended that you validate and customize any remediation steps to meet your organization's specific requirements and ensure that they align with your security policies and best practices.