Summary
In this chapter, we defined fault tolerance as a system’s ability to continue operating correctly despite component failures, differentiating it from high availability. We emphasized the importance of building resilient, fault-tolerant applications in today’s cloud environment. In the first section, we covered implementing redundancy by leveraging AWS infrastructure such as AZs and load balancing. We discussed the implications of stateless versus stateful application designs for fault tolerance. We saw how to use data redundancy strategies such as cross-AZ replication and backups, along with managed database services such as RDS, Aurora, and DynamoDB that provide built-in redundancy.
Furthermore, we learned that redundancy is not free, and that it often comes with increased complexity and costs. While it is essential for fault tolerance, it should be implemented judiciously, prioritizing the most critical components and aligning with business requirements and...
