Cluster

A group of servers and other resources that act like a single system and enable high availability and, in some cases, load balancing.

A cluster is a group of interconnected computers or servers that work together as a unified system to provide higher availability, improved performance, or both. Clusters distribute workloads across multiple nodes, so if one node fails, others can take over its responsibilities.

Clusters are commonly used in database systems, application servers, and container orchestration platforms like Kubernetes. They can be configured for high availability (failover clusters), load balancing (distributing traffic across nodes), or high-performance computing (parallel processing of large workloads).

In API infrastructure, clustering ensures that backend services remain available even during hardware failures or traffic spikes. While serverless platforms abstract away cluster management from developers, the underlying infrastructure still relies on clusters. API gateways themselves may be deployed as clusters to handle high request volumes and provide zero-downtime deployments.