RDS Certificate Authority Change

On August 22, 2024, old 2019 certificates are reaching EOL and need to be replaced (see below for full AWS notification details). I understand that I can modify the RDS instance and simple change the type under the Connectivity > Certificate Authority section, but how would I understand if my application will be affected by this change?

My application runs on ElasticBeanstalk with EC2 instances that connect to the RDS instance with the server hostname, username/password and port, but I'm not sure how to fully understand if modifying the RDS certificate will result in a lost connection or if this is just as simple as modifying the certificate type.

Can I test this with a dry run prior to making the change? Can I revert back to the original certificate immediately if there are issues? Do I need to consider updating any certificate files on the server itself, or in the EBS configuration?

All thoughts appreciated! Thanks.

--- AWS NOTIFICATION --- You are receiving this message because your AWS Account has one or more Amazon RDS, or Amazon Aurora database instances in the US-WEST-2 Region using an SSL/TLS Certificate that is expiring on August 22, 2024.

This is a follow-up notification for SSL/TLS CA certification expiration. If you believe you have already finished this work and still received this email it is likely because you created new instances using the 2019 CA. All newly created instances that don’t explicitly specify a different CA will use the 2019 CA until January 25, 2024 when the default will be switched to rds-ca-rsa2048-g1. For information on setting an account level CA override see the modify-certificates API documentation [1].

If your applications connect to these instances using the Secure Sockets Layer (SSL) or Transport Layer Security (TLS) protocol, you will need to take action before August 22, 2024 to prevent connectivity failures to your existing database instances. Even if you do not currently use SSL for your connections, you could still be affected if your databases server certificate expires, so we still recommend updating your CA.

To protect your communications with your database instances, a Certificate Authority (CA) generates time-bound certificates that are checked by your database client software to authenticate any database instance before exchanging information. Following industry best practices, AWS renews the CA and creates new certificates on a routine basis to ensure customer connections are properly protected for years to come. The current CA in US-WEST-2 will expire on August 22, 2024. Before this date you will need to update your DB server certificate. The general process to do this is:

First, update your application clients with the new certificate, if your application client is using trust stores then add the new CA certificates into the trust stores of your client applications. RDS provides download links to the CA certificates here [2]. For more detailed instructions on updating the trust stores on your client application see [3].

Second, update the certificate on all your affected database instances to one of the newly issues CA’s. rds-ca-rsa2048-g1 is the default recommended CA because there is no algorithm change. The other CA’s use new key algorithm’s so it could require more testing of your client setup to ensure compatibility. For more information on the new CA’s see [4].

Third, since the 2019 CA is still the default CA you will need to set an account level CA override so your new instances will use one of the new CA’s. To do this a modify-certificates API is available that will allow you to override the default CA on newly created database instances to either the old or one of the new CAs. This override will only apply while the CA you are overriding to is valid. To use this API you will need to be running the AWS CLI version 1.17 or later. For more information see the modify-certificates API documentation [1]. There is also a describe-certificates API [5], that will indicate your current default CA override if you have one set. To set a specific CA during instance creation use the ca-certificate-identifier option on the create-db-instance API is available for you to create a DB instance with a specific CA. For more information, see the create-db-instance API documentation [6].

For more detailed instructions on how to perform these updates please see the Amazon RDS instances [7] and Amazon Aurora instances [8] documentation.