Availability Patterns: Mastering System Design Interviews

Ensuring Robustness in Distributed Systems

In today’s digital age, system availability is paramount. Whether it’s an e-commerce platform or a cloud-based service, users demand seamless access without interruptions. But as systems scale and become more complex, ensuring high availability becomes a challenging task. This is where availability patterns come into play. These patterns are architectural blueprints that provide guidelines and solutions for building highly available distributed systems. In this article, we’ll delve into some of the most widely recognized patterns and how they work.

Failover Pattern

Definition: The failover pattern is about having standby or backup components that can take over in the event of a system failure.

How It Works: Imagine two servers: a primary and a secondary. Under normal circumstances, all traffic goes to the primary server. If the primary server fails, the system automatically reroutes the traffic to the secondary server. This process is often seamless, ensuring uninterrupted service.

Applications: This pattern is commonly used in database systems where a standby (or replica) database can take over if the primary database fails.