How does SSE scale across multiple server instances? What's the challenge and how do you solve it with Redis Pub/Sub?

Question

Tests whether you know a client's SSE connection is pinned to one server instance, so events must be fanned out to whichever instance holds that connection.

CrackLab · Accepted Answer

Tests whether you know a client's SSE connection is pinned to one server instance, so events must be fanned out to whichever instance holds that connection.

How does SSE scale across multiple server instances? What's the challenge and how do you solve it with Redis Pub/Sub?

Next Step