Software Architect's Handbook

Server-side discovery pattern

The other main pattern for service discovery is the server-side discovery pattern. The service client, such as an API gateway or another service, makes a request to a router. The router is typically a load balancer.

The following diagram illustrates the server-side discovery pattern:

In this pattern, it is the load balancer that queries the service registry for the locations of available service instances. The service registry may be built into the load balancer or it may be a separate component. The load balancer is then responsible for forwarding the request to one of the available service instances.

Unlike ...