Overview of Database Parameter Groups

Database parameter groups in AWS allow for the customization of the database engine through the setting of parameters. These parameters can be categorized into two types:

• Dynamic Parameters: Applied immediately without the need for rebooting the database instance.
• Static Parameters: Applied only after the database instance is rebooted.

It is also possible to switch the entire parameter group of a database instance, requiring a reboot for the changes to take effect. This feature is useful for moving from the default parameter group to a custom-created one.

Key Parameters for SSL Connections

• For PostgreSQL and SQL Server, the rds.force_ssl parameter set to 1 forces SSL connections.
• For MySQL and MariaDB, the require_secure_transport parameter set to 1 achieves the same purpose of forcing SSL connections.

Steps to Customize and Apply Parameter Groups

1. Accessing Parameter Groups: Located in the left-hand side panel of the AWS console.
2. Creating a Custom Parameter Group:
   • Select the appropriate database instance version.
   • Assign a name and description to the parameter group.
   • Customize parameters as needed.
3. Modifying Parameters:
   • Specific parameters like force_ssl can be edited to enforce SSL connections by setting their value to 1.
   • Dynamic parameters do not require a database reboot to apply changes.
4. Assigning Custom Parameter Group to Database:
   • Navigate to the database settings and modify the instance to use the new parameter group.
   • A reboot is necessary when changing to a new parameter group, which can be done immediately or scheduled during the next maintenance window.

Example: Enforcing SSL Connections for PostgreSQL

• Creating a Custom Parameter Group: Named group-demo-postgres for PostgreSQL version 10.4, with a focus on changing the force_ssl parameter.
• Applying the Custom Group: The custom parameter group is assigned to the target PostgreSQL database, requiring an immediate reboot to enforce SSL connections effectively.

Conclusion

This lecture outlined the process of customizing database engine behavior through parameter groups in AWS, highlighting the importance of dynamic vs. static parameters, and providing a step-by-step guide on creating, customizing, and applying parameter groups to enforce SSL connections for database instances.

Just like AWS Systems Manager (SSM) provides a unified interface for managing your EC2 instances, Parameter Groups in Amazon RDS provide a way to manage and apply database engine configuration settings across your fleet of DB instances.