How does a load balancer maintain session persistence across backend servers?

Example Concept: Session persistence is typically implemented by inserting a cookie into the client's session that uniquely identifies the backend server handling the session. This cookie is then used by the load balancer to route subsequent requests from the same client to the same server. Alternatively, source IP affinity can be used, where the client's IP address is hashed to determine the backend server. These methods ensure that all requests from a session are handled by the same server, maintaining state consistency.